Background: The incidence of syphilis is clearly increasing. It is a source of visceral damage, particularly in the secondary phase. Acute syphilitic hepatitis is a rare clinical entity classically described but under-diagnosed because of its non-specific presentation. Case Presentation: We report the case of a 25-year-old French woman, without comorbidity, sexually active, having unprotected sex with only one partner. She was admitted to our unit for jaundice and a disturbed liver function test preceded 3 weeks earlier by a rash. The patient did not consume alcohol and did not report the introduction of a new medication. A skin rash compatible with syphilitic roseola and generalized adenopathy were found. The liver workup showed alanine aminotransferase (ALT) at 1984 U/L, aspartate aminotransferase (AST) at 1377 U/L, total bilirubin at 221 μmol/L, alkaline phosphatase activity (APL) at 419 U/L, gamma glutamyl transferase activity (GGT) at 229 U/L and a prothrombin concentration at 73%. The search for the most common etiologies of acute hepatitis was negative. Syphilitic serology was positive with a Treponema Pallidum Hemagglutinations Assay (TPHA) titration of 5120 IU and Veneral Disease Research Laboratory (VDRL) of 64 IU. Abdominal ultrasound revealed only homogeneous hepatomegaly and splenomegaly with no focal lesions. Other sexually transmitted infections (STI) were negative and her partner had positive syphilis serology. After a single dose of Benzathine benzylpenicillin, the clinical signs regressed after one week and the hepatic balance tended to normalize 20 days later. Conclusion: This highlights the need for a high index of suspicion for syphilitic hepatitis in sexually active patients presenting with acute hepatitis associated with a cutaneous rash.