The purpose of this study is to develop conflict management considering justification of planning decision by public involvement (PI) in the context of Korea as an approach to prevent conflicts for railway projects and to achieve consensus building between public and governments. In this study, to evaluate the effectiveness of conflict management in the process of railway planning, we examined the before and after survey on the light rail transit (LRT) planning that was previously conducted. We first conducted estimation on the causal relationships among factors related to acceptance of LRT planning by structural equation model. The estimation results show that conflict management activities and acceptance are positively related. We also discussed as follows: the level of recognition of railway project influences positive effects regardless of conflict management activities, the most important factor with respect to the acceptance is awareness for planning necessity.