Integrating balance theory with self-perception theory, we propose that the incongruence between in-degree and out-degree centrality in a friendship network (centrality incongruence hereafter) contributes to the emergence of informal leadership. Through leadership emergence, centrality incongruence has a positive and indirect influence on organizational identification. In-degree centrality reflects the extent to which one is sought by others in the group as a friend, whereas out-degree centrality captures the extent to which one sees others as a friend. We surveyed 257 employees from 38 self-management business units at three observation points. Results based on polynomial regression and surface response analysis supported our hypotheses. Besides, the relationship between centrality incongruence and informal leadership emergence was stronger when the in-degree centrality is greater than the out-degree centrality compared to when the out-degree centrality is greater than the in-degree centrality. Our study points out the value of jointly considering in-degree and out-degree centrality in a social network in understanding their effects on leadership emergence and other work outcomes.