An uncommon case of Fournier's gangrene following hydrocelectomy is described. A 78-year-old male with no remarkable previous history, who underwent hydrocelectomy in another hospital, developed Fournier's gangrene 15 days later. The patient required wide aggressive surgical debridement, hyperbaric oxygen chamber and broad-spectrum antibiotic coverage. Afterwards the patient was referred for plastic surgery. Fournier's gangrene is a polymicrobial infection of perineoscrotal region that manifests as a rapidly progressive necrotizing fasciitis. Fournier's gangrene following hydrocelectomy is uncommon. The morbidity and mortality in this severe complication depend on early diagnosis and aggressive surgical management.