This study aims to identify which mechanisms of agglomeration economies have generated inter-regional wage gap between the capital region and the non-capital region in Korea. The mechanisms of agglomeration economies are divided into sharing, matching, and learning mechanisms. Based on the framework of the pioneering work of Glaeser and Maré(2001), we estimate a wage level effect and a wage growth effect by examining the wage patterns of migrants. The former effect implies the sharing mechanism and the latter effect implies the matching or learning mechanisms. Random effects models are used to estimate the wage pattern of migrants from the non-capital region to the capital region between 1998 and 2015. Since the positive correlation between unobserved ability and where to live leads to an upward bias in the estimate, we also use the Hausman and Taylor approach for valid estimation of the wage level effect. Our findings indicate that workers had experienced immediate wage growth shortly after migrating to the capital region. However, their wages did not grow gradually after migrating to the capital region. Among the three mechanisms, we conclude that the sharing mechanism best accounts for the inter-regional wage gap.