Since 2001, cases of hepatitis C virus (HCV) sexual transmission have been reported in France, among HIV-positive gay men who do not inject drugs. An earlier study focused on the incidence of acute hepatitis C and risk factors associated with HCV transmission. The present study, based on in-depth interviews, aimed to highlight the biography, the sexual practices and the experiences of gay men infected with HCV. Beyond an apparent uniformity, the group of interviewees illustrates a variety of situations, life stories and health pathways, depending on their age. These well-adjusted gay men were used to engaging in unprotected sexual practices, but before their diagnosis they largely ignored HCV-transmission risk, which was associated in their mind with a pejorative drug addict image. Once diagnosed with acute hepatitis C, they experienced a critical and emotional period during which they were open to discuss their sexual practices and reconsider risk-reduction procedures, without being willing to give up on their satisfying sex life. Health educators should consider labelling hepatitis C as an STI in order to disrupt its negative image and to help HIV-positive gay man raise their awareness of HCV-transmission risks and implement better risk-reduction strategies.