We examined the association of mothers’ thin-ideal internalization and children’s drive for thinness. Early adolescents (175 girls and 198 boys) completed a questionnaire to assess their drive for thinness and perceptions of mothers’ attitudes and behaviors related to body shape. The questionnaire for mothers (n = 206) measured mothers’ thin-ideal internalization. Mothers’ thin-ideal internalization was associated with girls’ drive for thinness through the perception of mothers’ attitudes directed to girls, and with boys’ drive for thinness through mothers’ weight-loss behavior. The findings suggest the possibility that mothers transmit social standards on body shape to their children.