Abstract Aims Engaging in self-care is an important aspect of the prevention and management of coronary heart disease (CHD), the leading cause of premature death in Thailand. As no validated tool exists to measure self-care in Thai people with CHD, we translated and examined the psychometric properties of the Self-Care of Coronary Heart Disease Inventory Version 3 (SC-CHDI-V3) in a Thai population. Methods and results The SC-CHDI-V3 was translated into Thai using the standard forward and backward translation procedure for self-care instruments. A cross-sectional design was used to examine the psychometric properties of the Thai version of the SC-CHDI-V3 in 250 patients with confirmed CHD in a tertiary hospital in southern Thailand. Cronbach’s alpha and McDonald’s omega coefficients were used to assess internal consistency, and confirmatory factor analysis was performed to assess construct validity. The Thai version of the SC-CHDI-V3 demonstrated acceptable internal consistency (Cronbach’s alpha and McDonald’s omega coefficients of each scale ranged from 0.821 to 0.910). Reliability estimates were adequate for each scale (range 0.863–0.906). Confirmatory factor analysis supported the original factor structure of the instrument, with good fit indices for all three scales (comparative fit index = 0.996–1.000; root mean square error of approximation = <0.001–0.040). Conclusions The Thai version of the SC-CHDI-V3 appears to be a valid and reliable instrument for measuring engagement in self-care maintenance, self-care monitoring, and self-care management among Thai people with CHD.