Previous research has identified exposure to interparental conflict (IPC) in childhood as a risk factor for young adults’ depression. However, there is still a lack of understanding of the underlying mediating mechanisms of this association. Driven by the spillover hypothesis, the present study investigated whether maternal antipathy and neglect, and in turn unmet psychological needs, mediated the relation between IPC and early adulthood depression in a sample of 347 undergraduate students (M = 23.27 years; SD = 0.86; 57.05% women) in China. The participants completed self-report measures of IPC, maternal care, satisfaction of basic psychological needs, and depression. Structural equation modeling revealed that: (a) IPC was positively associated with early adulthood depression; (b) this association was sequentially mediated by inadequate maternal care (i.e., antipathy and neglect) and by unsatisfied psychological needs. These findings suggest that efforts to prevent depression should focus on reducing not only IPC, but also inadequate maternal care and unmet psychological needs.