Focal myositis is an uncommon, self-limiting, benign skeletal muscle disease, which is generally determined as an inflammatory pseudotumor. The etiology is not fully known, although it has been suggested that subclinical damage may play a role. As it leads to a tumoral mass it may be confused with several diseases leading to incorrect evaluations. Definitive diagnosis is made by biopsy of the skeletal muscle. In radiologic diagnosis, magnetic resonance imaging is the most important modality. In this paper we presented the imaging findings of a 58-year-old female patient with focal myositis who was admitted with complaints of forearm swelling.