This study was to examine the effect of hotel employees` psychological empowerment(PE) on their pro social service behavior(PSB). In particular, this study investigated the mediating effect of role clarity(RC) on the causal relationships between PE and PSB. A critical review of available literature on the issues were presented and specific attention was paid to the mediating effect of role clarity which might work in between PE and PSB. The data for this study were collected from 142 employees who were working at 4 tourist hotels in Seoul. Hotel employees` PE was measured in terms of four dimensions such as competence (COM), self-determination(SD), impact(IM), and meaningfulness (ME). Results of aroian test indicated that the effect of ME on PSB was partially mediated by RC. and that the effect of IM on PSB was fully mediated by RC. However, the mediating effect of RC between COM and PSB was not statistically significant. Also the effects of SD on both RC and PSB was also not significant.