Objective  To systematically evaluate published methodological guidelines for health technology assessment (HTA) at home and abroad. Methods  Common electronic databases, guideline databases, international networks of HTA agencies/organizations, representative national HTA networks or official websites of governmental health departments were extensively searched and screened to identify guidelines for conducting or reporting HTA from inception to April 24, 2023. Basic information on guidelines, HTA processes, assessment indicators, reporting checklists and other information was extracted, analyzed and described using a systematic review methodology. Results  A total of 41 guidelines were included in this study, published from January 2002 to January 2023; the publishing institutions involved 23 countries/international organizations, 6 languages covered; and the assessment was mainly for all health technologies (n=23), pharmaceuticals (n=4), diagnostic/testing technologies (n=4), non-pharmaceutical health technologies (n=3), medical devices/equipment (n=3), hospital health technologies (n=2), medical and surgical interventions (n=1), and screening technologies (n=1); the assessment perspectives were mainly health system perspective (n=16), societal perspective (n=12), and hospital perspective (n=3), while the rest did not provide information on the perspectives; 28 guidelines described the detailed HTA assessment process, involving 11 steps; there were 39 guidelines described the assessment domains and related assessment indicators in detail, ranging from 2 to 9 assessment domains and involving 10 first-level assessment indicators; a checklist for HTA reports listed in 10 guidelines, involving 18 report entries; 17 guidelines reported conflicts of interest, mostly no conflict of interest (n=10), and 3 of the remaining 7 guidelines did not indicate a specific conflict of interest, while 4 guidelines in which possible sources of conflict of interest were indicated. Conclusion  The development of HTA has formed a relatively perfect assessment system, but there is a need to unify the criteria for classification of health technologies and reporting checklist, improve the specificity indicators for different types of health technologies, and clarify the assessment perspectives. Combined with the current situation of HTA development in China, contextualized guidelines for HTA implementation and reporting should be formulated to provide scientific information and methodological basis for decision-making on rational allocation of health resources.