This study illustrates communication activities between entrepreneurs and new business supporters in business incubation program. Empirical studies up to now revealed that building trust with client entrepreneurs is one of the key success factors for incubator performance; however, the contents of these communication activities and influence factors remained as further research topics. Based upon these problem recognitions, This study conducted interview research on incubation managers for deeper analysis on communication activities. The study hypothesizes that there would be an adequate "distance" in communication and that the combination of formal and informal communication forms is important. Evidence from this study indicates a number of important factors that would influence communication activities, and then the results of this study provide new viewpoints and implications in this field.