Hibernoma is a rare benign but metabolically active tumor of brown fat origin, that can have cross-sectional imaging characteristics similar to those of other fat-containing tumors, such as lipomas and liposarcomas, and its presence can lead to false-positive interpretation by exhibiting increased F18-fluorodeoxyglucose (F18-FDG) activity. A 46-year-old woman was diagnosed with dermatofibrosarcoma protuberans underwent F18-FDG positron emission tomography/computed tomography (PET/CT) for detecting recurrence after excision. F18-FDG PET/CT showed incidental intense uptake in the back in addition to increased F18-FDG uptake at the previous lesion site. To our knowledge, this is the first case report of intense F18-FDG uptake in hibernoma in Korea.