This study explored how belief in a just world (BJW) develops among Chinese adolescents and the predictive role of family factors.The development of BJW in adolescence is an important but understudied topic, especially in non-Western contexts.Using a three-wave longitudinal design, 1525 participants (48% girls; Mage = 12.47) were recruited to report their BJW, childhood SES, only-child or not, and parental psychological control in Wave 1 (Wave 2: N = 1262; Wave 3: N = 1124).The mean slope for personal BJW is positive and significant, but not significant for general BJW. Childhood SES predicted initial level of personal and general BJW and the rate of growth of personal BJW. Only-child predicted initial level and the growth rate of personal BJW. Parental psychological control negatively predicted personal and general BJW at three time points.Personal BJW increased during the observation period, whereas general BJW was stable. Individuals with lower levels of childhood SES had lower initial personal and general BJW but a higher growth rate in personal BJW than those with higher SES. Individuals having siblings had lower levels of initial personal BJW but a higher growth rate in personal BJW than those from only-child family. Parental psychological control may exert consistent and contemporaneous negative effect on BJW across time.