Crohn's disease is a chronic inflammatory bowel disease which affects mainly children and young adults, and its cause remains unknown so far. Infliximab, a monoclonal antibody to the pivotal cytokine tumor necrosis factor-alpha, has been approved as a drug for both induction and maintenance therapy for moderately to severely active, or fistula-complicated Crohn's disease. The authors report a 12-year-old male patient diagnosed as Crohn's disease complicated with a perianal fistula, which was refractory to the conventional therapy. After the 0, 2, and 6 week scheduled intravenous infusion of infliximab, the patient reached to clinical remission in both subjective symptoms and objective manifestations. For children or young adults who develop Crohn's disease in a refractory course, infliximab may serve as a drug which leads to a clinical improvement or even to an extent of remission.