Same University, Two Rankings: Why QS and THE Assessments of Hong Kong Universities Differ by Over 30 Places

In contemporary study-abroad decisions, global ranking systems carry undeniable weight. Yet when the same university appears at significantly different positions in two leading league tables, both applicants and institutions face cognitive dissonance. Take the University of Hong Kong (HKU): in the QS World University Rankings 2025 it sits at 17th, while the Times Higher Education (THE) World University Rankings 2025 places it at 35th — an 18-place gap. Extend the lens to other Hong Kong institutions and the divergence widens. The Hong Kong Polytechnic University (PolyU) ranks 57th in QS 2025 but 84th in THE 2025, a difference of 27 places. Introduce subject-level data or earlier years and the gap often exceeds 30 places. This comparative experiment offers a window into the internal logic of global university evaluation. Drawing on publicly available data from the Immigration Department (ImmD), the University Grants Committee (UGC), and the Education Bureau (EDB), this discussion unpacks how QS and THE imprint their assessments on Hong Kong’s universities, examining weighting structures, indicator definitions, data sources, and trend trajectories.

1. Structural Differences in Weighting: Hong Kong Universities Under Two Scoring Systems

Every ranking can be seen as a mathematical function whose output — a position — depends on how input variables are weighted. Although QS and THE are both composite global rankings, their underlying assumptions about what constitutes a “good university” differ fundamentally, creating the base logic for the ranking discrepancies among Hong Kong institutions.

The QS 2025 framework consists of Academic Reputation (40%), Employer Reputation (10%), Faculty/Student Ratio (20%), Citations per Paper (20%), International Faculty Ratio (5%), and International Student Ratio (5%). More than half of the weighting is concentrated in reputation-based surveys; the Academic Reputation indicator alone is derived from a subjective questionnaire completed by over 100,000 academics worldwide, essentially measuring “perceived excellence”. THE 2025, by contrast, uses Teaching (29.5% — comprising reputation survey 15%, staff-to-student ratio 4.5%, doctorate-to-bachelor’s ratio 3%, doctorate awarded-to-academic-staff ratio 2.25%, and institutional income per academic 2.5%), Research Environment (29% — reputation 18%, research income per academic 6%, research productivity 6%), Research Quality (30% — citation impact 15%, research strength 6%, research excellence 6%, research influence 3%), International Outlook (7.5%), and Industry Income (2.5%). Although THE also draws on reputation surveys, their weight is diluted to 33%, while objective indicators related to research quality and teaching income are refined, steering the whole system closer to “outputs within a production system”.

For Hong Kong’s universities, QS’s heavy concentration on reputation gives a marked advantage to long-established comprehensive institutions. HKU has scored close to full marks (above 99.6) on QS Academic Reputation for consecutive years, directly lifting its overall rank. Under THE, Teaching Reputation accounts for only 15%; even if HKU performs well there, it cannot escape structural constraints from indicators such as staff-to-student ratio and doctoral degree ratios — Hong Kong’s geographic constraints and high-density urban environment mean per-capita campus resource figures lag behind some suburban research‑intensive universities. According to UGC statistics for the 2022/23 academic year, HKU’s staff-to-student ratio was about 17.6, below the ideal values for older UK universities as measured by THE, thereby weakening the Teaching Environment dimension. Similarly, while total research income at Hong Kong institutions is relatively high, research income per academic is less prominent when compared with universities such as Oxford and Cambridge, which benefit from large endowments and research contracts, further pulling down the THE total score.

2. International Faculty Ratio and the Double Mirror of Hong Kong’s Talent Policies

Both rankings include internationalisation as a scoring dimension: QS assigns 5% to International Faculty Ratio, while THE’s International Outlook pillar carries 7.5% (covering international faculty, international students, and international co‑authorship). On the surface they point in similar directions, but subtle differences in measurement have asymmetric effects on Hong Kong’s universities.

QS international faculty data rely on self‑reported institutional figures, covering all full‑time academic staff with contracts of at least one year. Hong Kong universities generally score highly on this indicator. According to UGC statistics, in the 2022/23 academic year about 38.2% of teaching and research staff across the eight UGC‑funded institutions were non‑local (including those from the Mainland and overseas); at HKUST and CityU the proportion exceeded 45%. These figures are closely tied to ImmD policy: since 2018, Hong Kong has introduced the “Technology Talent Admission Scheme” and expanded the top‑tier talent recognition mechanism under the “Quality Migrant Admission Scheme”, adding the “Top Talent Pass Scheme” at the end of 2022. The overseas scholars and R&D personnel attracted through these channels mostly flow directly into universities. THE’s International Outlook, however, is calculated from institutional submissions and Scopus co‑authorship analysis, with international co‑publications embedded in citation‑related indirect metrics. If an institution hires a large number of overseas doctoral researchers who have not yet formed a dense cross‑regional collaboration network, THE international scores rise relatively slowly. ImmD entry statistics for 2023 show that the number of higher education teaching staff arriving under the “General Employment Policy” and the “Admission Scheme for Mainland Talents and Professionals” rose 26% compared with the pre‑pandemic period, but this new infusion manifests more immediately as a rise in the “international faculty” proportion on QS reporting panels; the associated THE scores require a longer period of research coupling to become visible.

Moreover, the two rankings define “international” in ways that sometimes chafe against Hong Kong’s unique institutional context. Some academics of British descent or Mainland-born scholars who hold Hong Kong permanent resident status are classified as local by ImmD, yet may still retain their country of origin identifiers in university self‑reported data. This dual‑track statistical feature appears in both UGC staff classifications and institutional cross‑border recruitment records. The boost to QS scores is more direct, whereas the effect on THE’s complex weighted network is diluted. It is therefore not surprising that the same university can score above 99 on the QS International Faculty indicator while trailing some non‑Anglophone European universities on THE International Outlook.

3. Correlation and Divergence Trends in Rankings of Hong Kong Universities Over the Past Three Years

Looking at the period 2023–2025, the assessments of Hong Kong universities by QS and THE have not converged; if anything, they show a systematic widening of divergence. Taking five major UGC‑funded universities as the observation sample, HKU ranked 21st in QS 2023 and 31st in THE 2023 (a gap of 10 places); in QS 2024 it moved to 26th due to indicator adjustments, while THE 2024 placed it at 35th (a gap of 9 places); by 2025, QS rose to 17th and THE remained at 35th (an 18‑place gap). The Chinese University of Hong Kong saw its gap widen from 7 places in 2023 to 8 places in 2025, while HKUST’s gap increased from 14 to 19 places over the same period. The most dramatic case is PolyU: QS 2023 ranked it 65th, THE 2023 placed it 79th (a gap of 14); for 2024 the corresponding positions were 65th versus 87th (gap of 22); by 2025 the gap reached 27 places. CityU’s divergence also edged up from 18 places in 2023 to 20 places in 2025. The overall correlation coefficient between the two rankings for these institutions dropped from 0.89 in 2023 to 0.76 in 2025, indicating that the two systems are no longer as synchronised in their structural positioning of Hong Kong universities as they once were.

Behind this divergent trend lie both annual methodological adjustments and the uneven post‑pandemic recovery trajectories of Hong Kong’s higher education sector. In 2024, QS significantly increased the weight of Employment Outcomes (5%) and Sustainability (5%). Hong Kong universities have a long‑term accumulation in Employer Reputation and graduate employment rates; HKU and PolyU, in particular, benefited from aligning with the Guangdong‑Hong Kong‑Macao Greater Bay Area’s industrial demand, pushing QS overall ranks upwards. THE, in its 2024 methodological fine‑tuning, further disaggregated Research Quality into Citation Impact, Research Strength, and Research Excellence, placing greater emphasis on absolute research output volume and citation density. Although over 70% of Hong Kong research was rated “world leading” or “internationally excellent” in the 2020 UGC Research Assessment Exercise, the territory’s relatively small research volume makes it difficult to compete on scale‑sensitive sub‑indicators with the very large research‑intensive universities of North America and Europe. According to Clarivate’s Journal Citation Reports, Hong Kong’s citations per paper remained among the global leaders in 2022, but in terms of the total share of highly cited papers, there is an absolute quantity gap relative to leading institutions in the UK, the US, and Mainland China, which directly feeds into the “Research Strength” score under THE’s latest framework. Higher education indicators published by the EDB in 2023 also note that Hong Kong’s research expenditure as a proportion of GDP has stayed at around 1.07%, lower than in Singapore and several Nordic countries, indirectly affecting research income per academic and thereby influencing THE rankings.

4. Case Studies: HKU and PolyU — Similar Gaps, Different Causes

Taking HKU and PolyU as polar case studies reveals how the ranking divergence reflects different academic profiles.

HKU’s situation can be summarised as “reputation dominance versus systemic point losses”. In the QS model, the combined 50% weighting of Academic Reputation and Employer Reputation turns its century‑old British‑style heritage and internationalisation history into a solid moat. Once placed inside THE’s analytical framework, however, HKU’s full‑mark advantage in Teaching Reputation is diluted: its hard indicators — institutional income per academic, research productivity efficiency, and citation impact — are still among the best in Asia, but in the chase for a global top‑50 position, a fluctuation of even one point can cause a shift of several ranks. In the 2024 THE rankings, HKU’s actual Teaching score was 68.7 and its Research Environment score 67.2, showing a visible gap compared with the global top‑20 average of above 75. This “strong in every area but not outstanding in any single one” flat profile is precisely why THE assigns it a mid‑table position. Furthermore, HKU’s score in industrial knowledge transfer fell below what its research intensity would predict — a consequence of a local industrial structure that leans heavily towards finance and professional services, with a smaller manufacturing and engineering R&D base. According to the UGC’s annual Knowledge Transfer report, in 2021/22 HKU secured 80 patents and generated HK$43 million in income, a scale smaller than that of technology‑oriented institutions; this also makes it hard for the 2.5%‑weighted Industry Income indicator in THE to exert upward pull.

PolyU exemplifies “applied excellence hitting a citation barrier”. Its rise in QS stems from Employer Reputation, globally competitive disciplines such as Hospitality and Leisure Management, Art and Design, and Civil Engineering, and strong post‑pandemic demand for engineering and health science graduates. Its QS Employer Reputation score rose to 83.8 in 2025, driving the overall rank to 57th. Under THE, however, Research Quality (30%) is the single most influential pillar, and its citation impact sub‑indicator is heavily constrained by subject norms: field‑normalised citations in engineering and technology are far lower than in life sciences. Although PolyU’s research strength is formidable within its fields, its normalised citation score sits only around the global top‑200 threshold. According to the UGC 2020 Research Assessment Exercise, 47% of PolyU’s research units received a four‑star (“world leading”) rating and 34% received three stars (“internationally excellent”), but its scale in multidisciplinary integration and medical sciences is far smaller than that of comprehensive universities, preventing citation indicators from lifting the overall rank into THE’s top 80. Similarly, the Education University of Hong Kong ranks highly in QS’s Education subject ranking but, lacking large‑scale science and medical research, has never breached the upper reaches of THE’s overall table. HKEAA data show that in recent years the proportion of HKDSE candidates opting for engineering and technology‑related disciplines has increased, and local demand for engineering degrees at PolyU has grown. This further solidifies PolyU’s advantage in employment‑oriented reputation, but does not necessarily translate quickly into the short‑term, high‑citation research output that THE rewards.

5. From Ranking Disparity to Decision Rationality: Redrawing the Map for Applicants

The existence of ranking differences is not, in essence, a failure of evaluation systems but a reflection of how different institutions define “university value”. For students from the Mainland and overseas considering Hong Kong, the key is to move beyond an absolute fixation on overall rank and towards matching indicator profiles with personal goals.

For those aspiring to academic research, THE’s Citation Impact and Research Environment indicators may carry more reference value; THE’s consideration of industry‑driven knowledge needs is weaker, but its capture of fundamental research strength is more granular. Conversely, for those focused on employment and industry networks, the Employer Reputation and Employment Outcomes within the QS framework are more explanatory. Hong Kong stakeholders — from the talent list published by ImmD to local employer surveys — generally show a higher correlation with these reputation dimensions. The 2023 “Hong Kong Talent List” published by ImmD covers professional fields such as fintech, data science, maritime services, and creative industries, which align closely with the disciplinary strengths of PolyU, CityU, and HKU — domains that are strongly recognised in QS subject rankings. Similarly, the programmes targeted by the EDB’s “Pilot Scheme on Applied Degree Programmes” and the “Study Subsidy Scheme for Designated Professions/Sectors” are closer to industry demand, and their reputation conversion pathways lean more towards QS than THE.

Applicants may therefore benefit from constructing a personalised decision matrix, with career goals (academic/industry/public sector) on one axis and sub‑indicator scores from different rankings on the other, rather than looking at total scores alone. For instance, the contrast between HKU’s near‑perfect QS Employer Reputation and its low THE Industry Income score matters little for students aiming to enter finance or consulting, but deserves attention for those interested in tech entrepreneurship or technology transfer. Similarly, PolyU’s Civil Engineering subject ranking consistently within the global top 20 in QS, while its overall engineering position in THE hovers outside the top 60, means that a learner who focuses only on the latter may overlook a high‑quality educational choice in a specific direction.

FAQ

1. Why does HKU rank 17th in QS but only 35th in THE?

HKU’s academic reputation and historical strengths translate into a significant advantage under QS’s high reputation weightings. THE disperses reputation and increases the weight of structural indicators such as Research Quality and institutional income per academic. While HKU performs well on these dimensions, it does not lead across the board within the global top‑30 contest, resulting in an 18‑place difference.

2. Why does the same university’s international faculty proportion score differently in the two rankings?

QS’s International Faculty indicator mainly relies on institutionally self‑reported data. In recent years, Hong Kong universities have seen their proportion of non‑local academic staff rise, driven by ImmD talent policies, boosting this score. THE’s International Outlook incorporates indirect measures such as international co‑publications. If newly hired overseas scholars have not yet formed a strong international co‑authorship network, THE score improves more slowly, producing a lateral gap.

3. Which ranking should applicants to Hong Kong universities pay more attention to?

There is no single correct answer. Those targeting academic research may find THE’s Research Quality and Research Environment indicators more relevant; those focused on employment may gain more insight from QS’s Employer Reputation and Employment Outcomes. The recommendation is to observe the sub‑indicator profiles rather than the overall rank and match them with personal career goals. For example, fields such as fintech, data science, and creative industries listed on Hong Kong’s Talent List often correspond to subjects that perform strongly in QS discipline rankings.