The purpose of this study was to validate the Thriving at Work Scale(TWS) developed by Porath and colleagues(2012) in Korea. Specifically, the study was attempted to (1) examine the factor structure and items of the TWS to develop the Korean version of the TWS(TWS-K), and (2) investigate the discriminant validity of the TWS-K with the 5 similar concepts proposed only conceptually in the literature(job engagement, flow, resilience, flourishing, psychological well-being) as well as the incremental validity of the TWS-K over job engagement on performance. Two surveys were conducted for this purpose, and a total of 850 employees working at different fields in Korea participated in off-line or on-line survey. In Study 1, we conducted both exploratory and confirmatory factor analyses using the off-line data of 205 participants. The results showed that the factor structure of vitality and learning composed of positive 10 items in the TWS-K had a better fit compared to the original positive 8 and negative 2 items included in the TWS. It was also found that the reliability of the TWS-K was much higher than that of the TWS among Koreans. In Study 2, the results of a confirmatory factor analysis on 645 on-line participants demonstrated the six-factor model which assumed the independence of 6 related factors had the best fit among 6 models, supporting the discriminant validity of the TWS-K. Support was also found for the criterion-related validity of the TWS-K on the various criteria of performance. In addition, the results of hierarchical multiple regression analyses confirmed that thriving at work is a distinct construct, as the incremental variances of thriving at work on task, contextual, and adaptive performance were significant when each of similar concepts such as jog engagement controlled. Finally the implications and future research directions were discussed based on the findings.