Highly active antiretroviral therapy (HAART) has been shown to have a beneficial effect on several opportunistic and other coinfections of HIV infected individuals. The effect of HAART on HCV coinfections is controversial. We describe the case of a patient, in whom a close temporal relationship between changes in HIV viremia, HCV viremia and ALT levels was observed. Longterm suppression of HIV replication by HAART was associated with a normalization of ALT levels and finally clearance of the HCV infection. Our data suggest that improved immune functions due to reductions of the HIV load led to a better control and finally resolution of the HCV infection in this patient.