ABSTRACT Child maltreatment is one of the most stressful and traumatic experiences that affect the development of children and adolescents. However, scant research has focused on promoting positive growth out of the traumatic experiences of this population. The current study aimed to apply the developmental assets model to a sample of maltreated adolescents from rural China to explore how to promote their positive growth and to understand the mechanism through which protective factors at various levels synergistically contribute to positive developmental outcomes. This study employed a cross‐sectional survey design and used a two‐stage clustered sampling method. A sample of 561 students who indicated maltreatment experiences was included for analysis in this study. Among them, 51.4% were female, aged 16.19 (SD = 1.50). The results of hierarchical linear regression analysis revealed that developmental assets, both external (family functioning, school connectedness and village engagement) and internal (resilience and meaning in life), contributed to positive developmental outcomes (life satisfaction, emotional well‐being and prosocial behaviours). The results of structural equation modelling analysis provided a good fit for the sample as a whole. The overall findings supported the hypotheses that higher levels of internal assets were associated with higher levels of developmental outcomes. Internal assets also mediated the effects of family functioning and school connectedness on three developmental outcomes. Unexpectedly, village engagement only showed a significant direct effect on prosocial behaviours. The findings highlighted the role of developmental assets and suggested that building developmental assets should be emphasized to promote positive growth of maltreated adolescents in China. Implications for theory, practice and policy are discussed.