The purpose of this study is to find out the relationships among organizational identity, organizational socialization, and organizational based self esteem. Organizational identity suggests the fundamental concept and comprehensive characteristics of the organization. Over the last quarter century, organizational identity has been established as the key concept in organization study and has explained a variety of organizational phenomena. Although the concepts of identity have produced a great deal of theoretical attention, empirical studies that examine their effects have been rarely published. This study analyzed the effects of organizational identity on members’ organizational based self esteem. The basis of social identity underlies the desire to improve and maintain self-esteem. And organizational socialization will moderate relationship between organizational identity and organizational based self esteem. This study made the research model based on the theoretical arrangement to explain these relationships between constructs. Using the collected data from 676 members at 53 organizations in South Korea, we tested and confirmed the construct validity and internal consistency by exploratory and confirmatory factor analysis, reliability by Cronbach's alpha. And we used hierarchical linear modeling (HLM) to test cross-level effects of hypothesized relationship. Multi-level research including cross-level research makes ourselves understood much of the nested complexity of real organizational life. Therefore, the multi-level perspective is important for organizational researchers to understand the complexity and richness of social phenomena that may emerge at different hierarchical levels. We used hierarchical linear modeling in HLM 7.01 to test the hypotheses. These models are intercepts as outcome models. Organizational identity was significantly related to organizational based self esteem. This result supported Hypothesis 1. As organizational identity became stronger, individuals tended to increase organizational based self esteem. The significance of coefficient associated with the interaction of organizational identity and organizational socialization supported Hypothesis 2. By drawing on theory and research from literature review and doing empirical analysis, the results supported the cross-level linkages between related variables. This research came to the conclusions to as follows: First, organizational identity of aggregating members' perception had positive effect on organizational based self esteem. Second, organizational socialization had moderating effect between organizational identity and organizational based self esteem. The findings suggest that organizational identity and socialization at the organizational-level is meaningful variable to understand individual attitude and behavior. Therefore, organizational management should endeavor to form favorable and distinctive organizational identity and concentrate on organizational socialization.