The current research examined Chinese parents’ motivation regarding music training for their children, and its relationships with their children’s learning outcomes (N = 269). Results of principal component analysis showed that Chinese parents had both intrinsic and extrinsic motivation regarding children’s music training. Parents’ intrinsic motivation was positively related to children’s learning achievement (rated by teachers). Although extrinsic motivation did not predict learning achievement, it served as a significant moderator and strengthened the relationship between intrinsic motivation and children’s achievement. Moreover, the results showed that children’s learning engagement mediated the interaction between intrinsic motivation and extrinsic motivation regarding children’s learning achievement. The corresponding moderated mediation model was supported. Theoretical and practical implications are discussed.