Purpose: Parents are important agents in the physical activity socializing process in children. The present study aims to examine the parental mediatory role in children's physical activity participation via a youth physical activity promotion (YPAP) model. Design/methodology/approach: A total of 872 Hong Kong Chinese children (aged ten to 13) in ten schools were invited to participate in the study. Their physical self-perception, physical activity perception, parental influence, and physical activity level were assessed. Structural equation modelling was employed to examine the relationship among the variables. Findings: The final model accounted for 18 per cent of the variance in children's physical activity participation. Parental influence imposed a direct ([beta]=0.19) and indirect effect on children's physical activity participation through the children's physical activity perception ([beta]=0.33) and physical self-perceptions ([beta]=0.19). Research limitations/implications: This study involved a cross-sectional design and data were collected over a single time frame; a cause-and-effect relationship among variables could not be drawn. Originality/value: The present study emphasizes how parental influence is related to children's physical participation. The information is useful for health professionals in the design of intervention programs to promote children's physical activity participation. (Contains 3 tables and 4 figures.)