<p>Despite recent advances in HIV prevention and treatment, black migrants from sub-Saharan Africa (SSA) in high-income countries remain disproportionately affected by HIV. Limited knowledge and stigmatising attitudes towards HIV often hinder testing, treatment uptake, and effective prevention. This study examined the socio-demographic and psychosocial factors of HIV knowledge and attitudes towards HIV among black migrants from SSA living in Australia. A cross-sectional survey was conducted between July 2024 and February 2025 among 319 black SSA migrants residing in Australia. The survey assessed HIV knowledge, attitudes towards HIV, acculturation, medical mistrust in Western health systems, conservatism, and key socio-demographic variables. Bivariate analyses and multivariable linear regressions were used to identify factors independently associated with HIV knowledge and attitudes towards HIV. This analysis showed that having a university education was independently associated with greater HIV knowledge, while longer duration of residence was inversely correlated with HIV knowledge in bivariate analysis. More conservative beliefs and higher medical mistrust in Western health systems were associated with more negative attitudes towards HIV, whereas higher HIV knowledge predicted more positive attitudes towards HIV. Findings underscore the critical role of both psychosocial and socio-demographic factors in shaping HIV knowledge and attitudes towards HIV. Culturally tailored interventions that build trust in health systems, support positive acculturation, and engage with community values to enhance HIV awareness and reduce stigma among black migrants from SSA in Australia.</p>