Behçet’s disease is a chronic multisystem inflammatory disease characterized by recurrent oral ulcer, genital ulcer and ocular inflammation. It affects mainly young adults ranging from twenties to forties, so the relationship between Behçet’s disease and pregnancy has been investigated in women during reproductive ages. In pregnant women, genital ulcers arise from infectious and noninfectious causes. We report a case of a Behçet’s disease with deep vaginal ulcer diagnosed for the first time during pregnancy.