Fournier's gangrene is life-threatening disease characterized by abrupt onset of a rapidly progressive necrotizing soft tissue infection involving the perineum and scrotum. In Fournier's original descriptions, the disease arose in healthy subjects without an obvious cause. Despite controversy still surrounds its etiology, current studies identify definite urologic and colorectal causes with its combined disease in a majority of cases. We experienced cases of large scrotal and perineal defect caused by Fournier's gangrene. Aggressive and extensive debridement with a parenteral broad spectrum antimicrobial agents was executed at the important points to the treatment. The patient also received adjuvant hyperbaric oxygen therapy. The clinical efficacy of hyperbaric oxygen was discussed. After control of infection and unavoidable loss of soft tissue, the major concern following Fournier's gangrene lies on the protection of the testicles and adequate volumetric scrotal appearance. The defect was successfully reconstructed with unilateral or bilateral gracilis muscle flap transposition and split- thickness skin graft. We present this article utilizing bilateral gracilis muscle flaps as an acceptable alternative in the approach to scrotal reconstruction in Fournier's gangrene.