Soft tissue hemangioma is a benign tumor which can be located within skeletal muscles. In case when the tumor is located close to bone structures, some periosteal reaction and cortical bone thickening can occur. The mentioned radiographically revealed symptoms, alongside with the palpable tumor, can lead to such false interpretation as a malignancy.

Purpose. To describe radiographic and MRI findings of the soft tissue hemangioma of the brachial muscles. Another purpose is to define the general features of the radiological diagnostics of soft tissue hemangioma.

Materials and methods. The article deals with the theoretical data and the facts of our own observation of the soft tissue upper arm hemangioma, which caused the periosteal reaction and the cortical bone thickening. The MRI examination was performed with the usage of the Hitachi Aperto Lucent MR scanner.

Results. The diagnosis was verified according to the results of the surgical intervention. The features of the radiological semiotic and the potential of the MRI in the diagnosis of soft tissue hemangioma are described.

Conclusion. The MRI is one of the applied methods for the diagnosis of the soft tissue hemangioma of the extremities. It is the most appropriate method to set the sizes and the shape of the tumor and to detect its relation with the nearest anatomical structures. It is important to pay attention not only to the tumor characteristics themselves but also to the presumable bone related changes.