INTRODUCTION: Rotavirus gastroenteritis is the leading cause of severe diarrhoea among young children < 5 years old. Previous cost-effectiveness analyses on rotavirus (RV) vaccination in Thailand have generated conflicting results. The aim of this current study is to evaluate the economic impact of introducing RV vaccination in Thailand, using updated Thai epidemiological and cost data.METHODS: Both cost-utility analysis (CUA) and budget impact analysis (BIA) of human rotavirus vaccine (HRV) under a universal mass vaccination (UMV) programme were conducted. A published static, deterministic, cross-sectional population model was adapted to assess costs and health outcomes associated with RV vaccination among Thai children