This study explores how marital status moderates the relationship between gender stereotypes and mental health in China. The findings reveal distinct impacts across different marital statuses, highlighting significant modulation by marital context: for cohabiting individuals, the negative effects are mitigated (coefficient = 0.143, p = 0.003), those in their first marriage experience diminished negative impacts (coefficient = 0.088, p < 0.001), and the effects are most pronounced for separated but not divorced individuals (coefficient = 0.223, p < 0.001). Significant sex-based differences include positive effects for women in first marriages (coefficient = 0.112, p < 0.05) and when separated but not divorced (coefficient = 0.234, p < 0.05), and for men post-divorce (coefficient = 0.167, p < 0.05). Gender stereotypes show a positive correlation with mental health for separated but not divorced individuals (coefficient = 0.445, p < 0.01), indicating that stereotypes paradoxically act as stabilisers in certain marital contexts.