Measurement of social and emotional skills in the Thai context confronts the issue of construct validity because the available theories and measures are developed from Western cultures where fundamental beliefs, customs, values, and ways of thinking differ from Thai culture. As such, they may or may not be suitable for use with Thai students. The Thai Social and Emotional Skill Rating Scale (TSESRS) is an instrument developed for school based utilities that measures social skills, emotional skills, and social cognitive skills reported by Thai students from upper primary to secondary grade. The TSESRS contains eight subscales which are Self Emotion Awareness, Other Emotion Awareness, Emotion Management, Assertion, Responsibility, Cooperation, Decision Making, and Problem Solving. The first three subscales belong to the Emotional Skill factor, the next three subscales are under the Social Skill factor, and the last two subscales measure Social Cognitive skills. This instrument is designed as a self-report rating scale with a 4 point Likert-scale. The final version contains 45 items including 5 negative items. Data were collected from 685 lower secondary students in 10 schools under the jurisdiction of the Phatthalung Educational Area, Thailand. The psychometric properties of this tool were analyzed using PRELIS and LISREL. The results revealed good to excellent psychometric qualities. Internal consistency reliability of scales and all items of TSESRS were higher than specified cutoffs. The composite score reliabilities of all but one subscale were greater than criterion. Intercorrelation between subscales shows unidimensionality of the TSESRS. It was also highly correlated with the materials published and used widely in the Western culture. As a result of Confirmatory Factor Analysis, a one-factor congeneric model of all subscales fits with the empirical data. The Confirmatory Factor Analysis was also conducted to investigate the factorial validity of three models, namely the three factor model, the one factor model, and the second order model. The results showed that the three-factor model, the proposed model of the TSESRS, was the best fit. Application of multiple group Confirmatory Factor Analysis also demonstrated invariance across gender of the TSESRS measurement model.