Fibrous hamartoma of infancy (FHI) is a rare benign tumor, which usually occurs within the first year of life. It is characterized histopathologically by organoid patterns; fibrous, adipose, and myxoid mesenchymal tissues. We experienced a case of FHI in a 2-year-old female. FHI occurred in the left buttock. MRI scans showed mixed intensity on T1 and T2-weighted images, and heterogeneous enhancement of Gd-DTPA. MRI findings suggested adipose tissues, fibrous tissues, and myxoid tissues. Therefore we consider that MRI scans are useful for diagnosis of FHI. The treatment for FHI is a marginal excision, but incomplete excision of FHI results in recurrence. FHI often has unclear boundaries of its margins, so we recommend adequate surgical margins for excision.
