Synovial sarcoma is an uncommon malignant soft tissue tumor which usually occurs in young-aged person, and frequently involves the lower extremities. Many authors recommended wide excision, adjuvant chemotherapy and radiation therapy. The proposed factors that affect the prognosis are age, size of tumor, site of tumor in the body, depth of tumor, histologic grade and method of treatment. The purpose of the study is to analyze the factors that affect the 5-year survival rate. We retrospectively evaluated 19 cases of synovial sarcoma treated in the Kosin University Medical Center from Jan. 1982 to Dec. 1994. The overall 5-year survival rate was 47.6% and the 5-year survival rates were significantly higher(P<0.05) in the group with smaller size of mass. The significantly lower 5-year survival rates were observed in the patient with deeply located lesion and with higher histologic grade. The 5-year survival rates were higher in the patients treated with wide excision than in the patients treated with amputation. But there was no significant difference between these groups. The adjuvant chemotherapy and radiotherapy were performed. In conclusion, we suggest that the better prognosis will be observed in the patients with smaller size of tumor mass, superficially located and lower histologic grade.