<p>Parental beliefs about mathematics are closely linked to the development of young children’s early math skills, yet the underlying mechanisms remain insufficiently understood. This study, situated within the Chinese cultural context, examines the relationship between two dimensions of parental math beliefs—Beliefs about Child Math Learning (BCML) and Beliefs about the Parent Role in Child Math Learning (BPRML)—and preschool children’s mathematical skills. It further explores the chain-mediating roles of home math activities and children’s math language in this relationship. Participants included 180 Chinese preschoolers (<i>M</i> _age = 62.26 months, SD = 4.36) and their parents. Data were collected through parent questionnaires and one-on-one child assessments, and analyzed using a chain mediation model. Results showed that both BCML and BPRML were significantly associated with children’s overall math skills. However, mediation analysis revealed a fully mediated pathway: once home math activities and children’s math language were included in the model, the direct associations between parental beliefs and children’s math skills became non-significant. Specifically, stronger parental beliefs were associated with more frequent engagement in home math activities, which in turn were associated with more advanced math language and higher mathematical proficiency in children. These findings suggest that the link between parental math beliefs and children’s math skills is best explained by an indirect pathway: beliefs → behavior → language → skills. Within this pathway, home math activities provide a critical context for parental involvement, while children’s math language serves as a key conduit connecting the home environment to individual cognitive development.</p>