Like many countries in sub-Saharan Africa, Mozambique is facing a severe HIV epidemic. Evidence suggests that male sexual behaviour is one of the driving forces behind the epidemic. Yet, there is limited understanding of how notions of masculinity influence such behaviour in the context of HIV. Using data collected through focus group discussions and in-depth interviews with sexually active men and women, this paper investigates how notions of masculinity influence the risk of HIV infection among men. The study findings suggest that traditional norms of masculinity, the man as the main provider and figure of authority, continue to exert a strong influence on male attitudes and behaviour. Alternative approaches are urgently needed in HIV programming that take into consideration notions of masculinity in order to reduce risky sexual behaviour.