Objective To investigate the clinical characteristics of primary malignant tumors of the left atrium and the late results of surgical treatment. Methods The clinical experience with surgical treatment of 13 primary malignant tumors of left atrium was analyzed retrospectively. Complete resection of malignant tumor was achieved in 7 cases(53.8％ )，and subtotal resection was achieved in 3 cases(23.0％), only biopsy was performed in 2 patients(15.4％ )because of extensive metastasis of tumor. Heart transplantation was performed in 1 case(7.7％). Results There was no hospital death. The pathological diagnosis was undifferentiated sarcoma in 5 cases, leiomyosarcoma in 2 cases, malignant transformation of myxoma in 2 cases, angiosarcoma in 1 case, fibrosarcoma in 1 case, malignant fibrous histocytoma in 1 case and malignant hemangiopericytoma in 1 case. There were 11 patients followedup for 3 months to 65 months and showed 9 late death due to recurrence or metastasis. There was 2 patients lost of follow-up. Conclusion Primary malignant tumors of the left atrium should be resected to relieve symptoms caused by local tumor growth. Surgery provides control of primary tumor and allows the potential for cure or longterm survival with effective adjuvant therapy. The prognosis of these patients is still poor.