The wellbeing of parents of children with autism residing in mainland China remains understudied. We aimed to examine whether and how parental perceived social support, individualism, and collectivism acted together to moderate the relationships between child behavior problems and parental psychological distress in Chinese parents of children with autism. With convenience and snowball sampling, data on 268 primary caregiver parents of children with autism were collected from an online cross‐sectional survey. Linear regression analysis indicated that child behavior problems were significantly associated with increased psychological distress in Chinese parents of children with autism. There was no evidence to support the stress‐buffering model of social support in moderation analysis of the association between child behavior problems and parental psychological distress. Nonetheless, increased social support was associated with lower levels of parental psychological distress. Moderated moderation analyses did not support a role for individualism or collectivism as a moderator of the putative buffering role of social support. However, there was evidence that parental individualism was associated with increased parental psychological distress. Our findings highlight that child behavior problems are a robust correlate of parental psychological distress, and parental social support may act as a compensatory factor promoting less psychological distress rather than having a protective role. The role of social support and cultural values in the wellbeing of parents of children with autism in China requires additional exploration, including longitudinal research designs.