Herpes simplex virus type 2 (HSV-2) HIV co-infection is common and associated with increased risk of HIV transmission. HSV-2 seroprevalence was assessed on stored samples from baseline and one year follow-up from 81 patients identified with acute HIV infection and 81 age-matched chronically infected men. HSV-2 seroprevalence at baseline was lower for those with acute rather than chronic HIV-infection, 51.9 versus 71.6% (P = 0.01); relative risk 0.72 (95% confidence interval [CI] 0.57-0.92). Since HSV-2 seroprevalence is lower in those newly HIV-infected, the diagnosis of early HIV infection may allow for counselling to reduce subsequent HSV-2 acquisition.