To investigate histologic prognostic factors in soft tissue sarcomas (STS), multivariate analysis was performed on 236 patients with complete clinical information. These included 141 males and 95 females with an age range from 1 to 85 years (median, 47.6 years). Histologically, malignant fibrous histiocytoma (33.5%) was the most common type followed by synovial sarcoma (11%), liposarcoma (10%), rhabdomyosarcoma (7%), and leiomyosarcoma (7%). Monofactorial analysis revealed that sex, depth, location, histologic grade, cellularity, frequency of mitosis, and necrosis were significant prognostic factors. By multivariate analysis, only frequency of mitosis and depth of tumors were proved to be of prognostic significance. The prognostic importance of the frequency of mitosis as shown in previous and the present studies indicates that further investigation of the cell proliferation in patients with STS is required.