A keloid is a benign fibroproliferative disease of unknown etiology. Although it is common among Asians, the development of keloid on the foot is rare. We experienced a case of a keloid which arose on the foot of a 4-year-old boy after the surgical release of syndactyly. He had congenital cutaneous syndactyly of the third and fourth toes. After the reconstructive operation was performed when the patient was 2 years old, the wound became hypertrophic and grew to 37 × 37 × 8 mm. After the diagnosis of keloid based on a pathological examination, the keloid was resected completely. The web was reconstructed with a planter rectangular flap, and the skin defects were covered with a full-thickness skin graft. After the operation, we administered 5 intralesional steroid injections. Finally, the keloid was diminished 2 years after the operation.