Objective: To explore the association between pubertal timing and social adaptability in junior school students, and to provide guidance for adolescent psychological education and behavioral interventions. Methods: From September to December 2021, 3 591 junior school students were selected from four cities in Henan Province through stratified cluster sampling. The data were obtained with questionnaires of the Youth Development Scale and Social Adaptation Scale. Results: The scores of psychological advantage, mental energy, interpersonal adaptation, psychological elasticity and social adaptation were significantly higher in boys than girls( t =2.03, 5.64, 2.48, 3.65, 4.01, P <0.05). One way ANOVA indicated that the scores of social adaptation in the delayed group were significantly higher than those in the moderate group, and those in the moderate group were significantly higher than those in the advanced group( P <0.01). Multiple linear regression analysis demonstrated that, as compared with the moderate group, the group with early puberty showed negative correlations with psychological advantages, mental energy, interpersonal adaptation, psychological resilience and total social adaptation score( β =-0.30,-0.31,-0.31,-0.32, -0.35, P <0.01). Conclusion Pubertal timing among junior school students is closely associated with social adaptation. Early puberty negatively influences social adaptability. Schools are recommended to take scientific measures to strengthen psychological assistance for students who enter puberty early and to improve their social adaptability.