To investigate the prevalence of syphilitic hepatitis among a group of HIV-infected patients we performed a cross-sectional observational study of consecutive HIV-infected patients with early syphilis attending University Hospital Birmingham between 1 January 2005 and 31 August 2008. The AIDS Clinical Trials Group grading for abnormal liver enzymes was used to identify hepatitis. A total of 62 HIV-infected patients were diagnosed with early syphilis during the study period. Twelve (19.3%) of them demonstrated abnormal liver enzymes consistent with syphilitic hepatitis involving raised levels of alanine aminotransferase, aspartate transaminase, alkaline phosphatase or gamma-glutamyl transferase (GGT). Grade 3 hepatotoxicity was observed among five patients. None of the patients with syphilitic hepatitis had grade IV hepatitis or abnormal bilirubin levels. Liver biopsy was not carried out in any of the patients, and following completion of treatment of syphilis all abnormal liver enzymes returned to normal levels after a median of 16 weeks. Exclusion of syphilis must be considered when investigating hepatic disease in HIV-infected patients.