Using research data gathered from multiple sources, the current study explored positive aspects of peer relationship profiles (indexed by peer-nominated acceptance and self-reported friendships) in a person-centered approach among early adolescents from low-income families. Moreover, this study investigated the unique and combined associations of adolescents’ attachment to mothers and parent-rated conscientiousness with emerging peer relationship profiles. A total of 295 early adolescents (42.7% girls; Mage = 10.94, SD = 0.80) were involved in this study. Latent profile analysis identified three empirically derived peer relationship profiles: “isolated” (14.6%), “socially competent” (16.3%), and “average” (69.1%). Moderation analyses further showed that adolescents with secure attachment to mothers tend to have group memberships in socially competent and average profiles than the isolated profile. Such an association pattern was more heightened for those with higher conscientiousness (versus lower conscientiousness).