This study aimed to investigate the relationship between parental autonomy support and children’s self-concept, and to explore the role of basic psychological needs in Chinese primary schools from the perspective of self-determination theory. A total of 3109 children aged 6–13 years participated in eastern China. The results indicated a significant correlation between parental autonomy support, basic psychological needs, and children’s self-concept. Basic psychological needs play a partial mediating role between parental autonomy support and children’s self-concept. Specifically, autonomy support varied by need types whereas parental control steadily played a negative predictive role. Parental autonomy support and control predicted children’s self-concept differently through three basic psychological needs, with differences across gender and grades. Boys and elder children had stronger relationships to competence needs, while girls were sensitive to autonomy needs; in addition, both of them were sensitive to relatedness needs. The mediating effects model and cross-group analyses revealed the complex predictive role of parental autonomy support on children’s self-concept in China, providing an effective entry point for cross-cultural research and family education to improve children’s psychological well-being.