<p>In gender-imbalanced China, migrant populations are a high-risk group for HIV transmission. Informed by the social–ecological model, this study investigated the association between egocentric sexual networks and HIV sexual behavior patterns, evaluating the moderating effects of migration experiences and neighborhood characteristics among male migrants in China’s gender imbalance context. Data from two cross-sectional surveys conducted in 2017 in China, targeting never-married men in rural areas and male migrants (married and unmarried) in urban settings, were collected. The study included 713 respondents aged 28 and above with rural household registration (hukou) and migration experience. Utilizing latent category analysis, based on their sexual risk behaviors, 33.4% of respondents were classified into high-risk patterns for HIV infection. Multivariate logistic regression models showed that egocentric sexual network characteristics, including sexual network size, partner age, and partner type, were significantly associated with high-risk HIV sexual behavior patterns. Residence in high-risk neighborhoods reinforced or strengthened the association between egocentric sexual networks and high-risk patterns, but migration experiences weakened this association. The analysis revealed heterogeneity in HIV sexual behavior patterns and associated factors between never-married and married male migrants, highlighting significant implications for HIV prevention efforts targeting populations facing the challenges of gender imbalance. Policymakers and public health providers should incorporate egocentric sexual network factors associated with HIV risk, as well as the roles of neighborhood characteristics and migration experiences, into the consideration of comprehensive HIV intervention.</p>