Abnormal liver function before allogeneic BMT has been associated with VOD. Hepatitis G virus/GB virus C (HGV) is a recently discovered virus suggested to be a cause of non-A, non-B, non-C, non-D and non-E hepatitis. The aim of this retrospective study was to analyze the risk for liver complications and time to engraftment in patients infected with HGV. Fifty patients transplanted in 1995 were examined with RT-PCR for HGV on samples collected before, and between 3 and 6 months after BMT. Seven patients had HGV detected before BMT. No patient became infected during or early after the BMT. There were no differences in either pre- or post-transplant liver function abnormalities, VOD, or time to neutrophil engraftment in patients who did or did not have HGV detected before BMT. We conclude that the importance of HGV infection for the development of post-transplant complications is limited.