After being socially excluded, people try to reconnect with others. Previous research indicated that excluded people show an enhanced ability to distinguish between-category differences relative to within-category differences of group members. It is important that excluded people distinguish in-group members from out-group members to avoid making an unnecessary effort for social reconnection or further ostracism, because in-group members afford more opportunities to reconnect compared with out-group members. We hypothesized that this perceptual change would heighten the perception of the similarity of group members. Participants were included or excluded by Cyberball (a ball-tossing computer game) and constructed imagined histograms of the perceived distribution of members of four groups across a trait dimension. As predicted, social exclusion heightened the participants’ perception of the similarity of group members.