The purpose of this study was to examine how the preschooler, who could not get used to a kindergarten at the beginning of entrance, formed peer relationships by changing dependent behaviors to the specific others. Behaviors in the free playtime from the beginning of the entrance to the end of summer vacation were observed, and the dependent behaviors to the specific others were analyzed. For the analysis of dependent behaviors, this study used network analysis and case analysis, after serially analyzing the rate of dependent behaviors. Consequently, the five serial changes of following were shown : (1) the dependence to a teacher (2) the dependence to a specific friend (3) "relationship" to a specific friend (4) widening the peer relationships to other friends (5) peer play while prizing a specific friend. This study also found that in order to make this change happen, the "relationship" with target of dependence was required. Finally, for preschooler to get used to a kindergarten and to enrich peer relationships, this study may suggest that the existence of the target of dependence will be important.