In this study, 302 junior high school students aged 12 to 15 were selected as the research objects to investigate the overall situation of parental education investment, parent-child relationship and social development level of junior high school students. Simultaneously, the relationship between parental education investment and parent-child relationship and adolescent social development level was investigated. The results indicate that significant differences exist in the level of social development between adolescents with high scores and those with low scores. whether it is parental education involvement or parent-child relationship. There is a significant positive correlation between parental education involvement and parent-child relationship, parental education involvement and adolescent social development, parent-child relationship and adolescent social development; among them, parent-child relationship plays a significant mediating role in the path of parental education involvement affecting adolescents ' social development. Therefore, we should increase the participation of parents in education and strengthen the construction of parent-child relationship to promote the social development of adolescents.