["Journal of Intellectual Disability Research, EarlyView. ", "\nABSTRACT\n\nBackground\nDrawing on Darling and Steinberg's integrative model of parenting, this study investigated the influence of parental support (companionship and modelling) on the physical activity levels of children with intellectual disabilities, with a specific focus on the moderating role of different parenting styles.\n\n\nMethods\nA cross‐sectional survey was conducted using a convenience sample of 191 parents of children with ID in China. Data were collected via parental support scales, the short form of the International Physical Activity Questionnaire (IPAQ‐S) and a parenting style questionnaire. Hierarchical regression analysis was employed to test the main effects of parental support, and the PROCESS macro (Model 1) with the bootstrap method was used to examine the moderating effects of parenting styles.\n\n\nResults\nBoth parental companionship (B = 865.62, p < 0.001) and parental modelling (B = 829.79, p < 0.001) were significant positive predictors of children's physical activity levels. Moderating effect analyses revealed that a democratic parenting style significantly enhanced the positive effects of parental support. In contrast, an inconsistent parenting style significantly weakened the positive effect of parental modelling (Coeff = −579.22, p = 0.007). The interaction with parental companionship showed a similar negative trend but was marginally significant (p = 0.057), indicating a need for further verification. Other nondemocratic parenting styles (authoritarian, permissive and indulgent) showed no significant moderating effects.\n\n\nConclusions\nParental support is a key predictor of physical activity in children with intellectual disabilities, but its effectiveness is significantly moderated by the family's parenting context. A democratic parenting style acts as a ‘catalyst’, optimizing the impact of supportive behaviours, whereas an inconsistent parenting style acts as an ‘inhibitor’, particularly weakening the effectiveness of role modelling. The findings suggest that health promotion interventions for this population should adopt a dual‐focused strategy: guiding parents to provide specific support behaviours while simultaneously fostering a democratic and consistent parenting climate.\n\n"]