IntroductionCost-utility analysis (CUA) is the preferred form of economic evaluation in many countries. As one of the key data inputs in cost-utility models, health state utility (HSU) has a crucial impact on CUA results. In the past decades, health technology assessment has been expanding rapidly in Asia, yet research examining the methodology and process used to generate cost-effectiveness evidence is scarce. The aim of this study was to examine the reporting of the characteristics of HSU data used in CUAs in Asia and how the characteristics have changed over time.MethodsA systematic literature search was performed to identify published CUA studies targeting Asian populations. Information was extracted for both the general characteristics of selected studies and the characteristics of reported HSU data. For each HSU value identified, we extracted data for four key characteristics, including 1) estimation method; 2) source of health-related quality of life (HRQoL) data; 3) source of preference data; and 4) sample size. The percentage of nonreporting was calculated and compared over two time periods (1990–2010 vs 2011–2020).ResultsA total of 789 studies were included and 4,052 HSUs were identified. Of these HSUs, 3,351 (82.7%) were from published literature and 656 (16.2%) were from unpublished empirical data. Overall, the characteristics of HSU data were not reported in more than 80% of the studies. Of HSUs whose characteristics were reported, most of them were estimated using the EQ-5D (55.7%), Asian HRQoL data (91.9%), and Asian health preferences (87.7%); 45.7% of the HSUs was estimated with a sample of 100 or more individuals. All four characteristics showed improvements after 2010.ConclusionOver the past two decades, there has been a significant increase in CUA studies targeting Asian populations. However, HSU’s characteristics were not reported in most of the CUA studies, making it difficult to evaluate the quality and appropriateness of the HSUs used in those cost-effectiveness studies.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12955-023-02131-z.