Childhood trauma has been identified as an important etiological risk factor for depressive symptoms, but there are other modifiable social environmental factors that may be equally, if not more, important. This study aimed to improve our understanding of the social determinants of depressive symptoms among young people while taking childhood trauma into account. We analyzed survey data from a convenience sample of Chinese young adults aged between 18 to 24 (N = 205). Participants completed standardized assessments of childhood trauma (the Brief Betrayal Trauma Survey), depressive symptoms (the PHQ-9), and social environmental stressors (the Social Environmental Stress Questionnaire). Social environmental stressors had the strongest relationship with depressive symptoms (β = .416, p < .001), above and beyond the effects of childhood trauma. We also identified some specific modifiable and targetable social environmental stressors (e.g., school work and occupation issues, high expectations from others, sleep environment) that were positively correlated with depressive symptoms, even when the Bonferroni correction was applied. Although childhood trauma is a well-documented risk factor for mental health problems, there are modifiable factors associated with depressive symptoms, above and beyond the effects of childhood trauma. Educators, healthcare practitioners, social service providers, and policymakers can play a vital role in changing the trajectory of depression in the community.