The present study was intended to investigate the characteristics of coalition formation processes in the competition for power precedence, focusing on the phase where motivation to defend status was dominant. Subjects, 90 male undergraduates, were divided into 30 groups of three persons each and were assigned to each rank order of power such as TOP, MIDDLE, and BOTTOM. Then they were confronted with the task to form two person coalition to obtain new resources for promoting their power ranks. Although TOP always preferred BOTTOM as a coalition partner and BOTTOM preferred TOP any time, MIDDLE changed his preferable partner depending on the probability that he could recover in the future if he lose his rank. While high probability motivated MIDDLE strongly to promote his rank and to select BOTTOM as his coalition partner, low probability motivated MIDDLE intensely to defend his status and to make large concessions to TOP to let TOP select him. Consequently, coalitions consisting of TOP and BOTTOM were formed more frequently on high probability condition, but coalitions consisting of TOP and MIDDLE more frequently on low probability condition.