OBJECTIVES: To develop a Thai version of the Audit of Diabetes-Dependent Quality of Life (ADDQoL-19) and to evaluate its psychometric properties among Thai patients with diabetes. METHODS: This study was conducted by firstly cross-culturally adapting the original English ADDQoL-19 into Thai, followed by administering the Thai version together with the Thai EQ-5D and sociodemographic questionnaire to patients (aged >18 years) with diabetes recruited from a tertiary hospital in central Thailand by simple random sampling. The usefulness of a ‘not applicable’ (N/A) option and the necessary of weighting the impact scores, factor structure and internal consistency reliability of the Thai ADDQoL-19 were assessed. Data were subjected to confirmatory factor analysis (CFA) using structural equation modeling (SEM) and exploratory factor analysis (EFA) using principal component analysis (PCA). The known-groups validity of the Thai ADDQoL was assessed by four a priori hypotheses. RESULTS: The Thai ADDQoL-19 was shown to be conceptually equivalent to its original version and culturally relevant to Thai patients with diabetes. Its psychometric properties were evaluated among 201 diabetic patients (71.1% females; 81.6% primary educated; mean age 54.25 [SD=9.8] years). Its unique characteristics, i.e., weighting and individualization were proved to be necessary for a more accurate assessment of quality of life. The Thai ADDQoL-19 also demonstrated a good internal consistency reliability, with the Cronbach’s alpha of 0.90. However, the fit indices derived from a CFA failed to achieve a good fit (i.e., >0.90).  EFA with forced-one factor solution showed factor loadings above 0.40 for all items, except for sexual relationship. The known-groups validity was also not clear as only two hypotheses were fully fulfilled. CONCLUSIONS: The Thai ADDQoL-19 has shown to be culturally appropriate and highly reliable but requires further investigations to provide more evidence on its factor structure and known-groups validity before its utilization in routine clinical settings.