Monkeypox (mpox) has emerged as a global public health concern, particularly among men who have sex with men (MSM). Stigma limits access to care, and the role of social support in shaping care-seeking through psychosocial mechanisms remains unclear. This study examined whether social support influences care-seeking intentions via stigma and perceived healthcare benefits among MSM in China.A cross-sectional study was conducted from October 2023 to March 2024 across 6 provinces in China. Descriptive statistics, chi-square tests, Spearman correlations, and logistic regression were performed to explore associations between HBM-related constructs and healthcare-seeking intentions. Structural equation modeling was used to examine the direct and indirect effects of social support via stigma and perceived healthcare benefits.Among participants, 83.4% expressed an intention to seek healthcare for mpox. Directly, social support was positively associated with healthcare-seeking intention (β = 0.274, p < 0.001). Indirectly, social support affected healthcare-seeking intention through two pathways: (1) by reducing stigma (β = -0.108, p < 0.001), which in turn enhanced perceived healthcare benefits (β = -0.663, p < 0.001), ultimately increasing healthcare-seeking intention (chain effect β = 0.033, p = 0.005); and (2) directly enhancing perceived healthcare benefits (β = 0.091, p < 0.001), thereby increasing healthcare-seeking intention (β = 0.231, p < 0.001; indirect effect β = 0.042, p = 0.005). The total indirect effect accounted for 22.6% of the total effect.Social support enhances mpox care-seeking intention among MSM in China by reducing stigma and improving perceptions of privacy, affordability, and treatment efficacy. Integrated interventions-combining peer support, stigma reduction, and privacy protection-are needed to foster early health engagement.© 2025. The Author(s).