A malignant fibrous histiocytoma of the mesentery is rare, and multifocal involvement as a primary tumor is very rare. In this report, a case of malignant fibrous histiocytoma of the mesentery presenting with two masses and multiple peritoneal seeding in a 48-year-old man is described. A physical examination revealed a large, firm, and non-tender mass in the right lower abdomen of the patient. Computed tomography of the lesion revealed a partially, indistinctly marginated and heterogeneously enhancing mass with irregular peritumoral strands in the mesentery of the right lower abdomen, while sonograms of the lesion revealed an ill-defined low-echoic mass. The final pathology demonstrated the presence of a storiform-pleomorphic malignant fibrous histiocytoma.