The origins of self-criticism were investigated with 507 participants. A questionnaire assessed parental behaviours, attachment, peer victimization, and self-compassion. Multiple linear regression analyses were employed to assess parental attachment’s association with self-criticism, parental criticism’s mediating effects, and moderating effects of self-compassion, peer victimization, gender, parental substance abuse, and parental divorce. Low parental attachment predicted self-criticism; maternal criticism mediated maternal attachment’s effects on self-criticism; peer victimization moderated paternal attachment’s effects on self-criticism; and maternal substance abuse moderated maternal attachment’s effects on self-criticism. Self-compassion, parental divorce, and gender did not moderate any relationships. Secure attachment to parents decreased participants’ likelihood of developing self-criticism; protective factors of paternal attachment appear vulnerable to peer victimization; and maternal influences on the development of self-criticism may reflect that mothers being more influential than fathers in molding how their children view themselves and others. Results may reflect qualitative or quantitative differences in mothers’ relationships with their children.