Aggressive fibromatosis is proliferation of well‐differentiated fibroblasts. Submandibular region is rare location for fibromatosis. We report a case of a rapidly growing mass in submandibular region of 5‐year‐old girl, excised surgically and ascertained to be aggressive fibromatosis on histological examination. Recovery was uneventful, and she was disease‐free in 6‐month follow‐up.