Pyoderma gangrenosum is characterized by a chronic, non-infectious, destructive ulcer which is mostly seen on distal lower extremities, but it can be found anywhere on body. We report an 18-year old man who developed keloids after healing of his ulcers. He was a known case of chronic relapsing pyoderma gangrenosum. His previous ulcers were used to heal leaving atrophic, cigarette-paper scars. But since a year ago, following using clofazimine for his disease, he has developed keloids after healing the ulcers. Alterations in the immune system of the patient might be involved. Development of keloids in ulcers of pyoderma gangrenosum has not been reported previously.