Perceived physical competence can be an important predictor of the physical activity behavior of children and adolescents. Investigated in this study was the role of mothers' expectancies effects in shaping their child's perceived physical competence. Data were obtained from 156 French children and young adolescents and their mothers. Structural equation modeling revealed that mothers' perceptions of their child's physical competence predicted their child's own perceived physical competence one year later, independent of the child's previously demonstrated physical ability and the child's initial level of perceived competence. Child's gender moderated the relation in that mothers' perceptions of their daughters' competence were related significantly to their child's perceived competence but that relation was not present between mothers and sons.