Dermatofibrosarcoma protuberans (DFSP) is a rare cutaneous tumor with a possibly misleading presentation. It is rare in childhood. We report an 18-month-old child with an acquired atrophic plaque of the left ankle. Based on clinical findings, initial proposed diagnoses included localized scleroderma and localized lipoatrophy. At the age of 5 years the plaque had increased in size and become a purplish color. Several firm nodules were seen at its periphery. A diagnosis of DFSP was proposed and confirmed histologically. A large surgical resection was performed. This case illustrates that DFSP may occur in childhood, during which initial diagnosis is generally more difficult than in adulthood.