Malignant mesenchymomas by definition are composed of two or more cellular types that would ordinarily derive from primitive mesenchyme. They grow rapidly, recur frequently, metastasize, and can be found in a wide variety of locations. Malignant mesenchymomas as primary cardiac tumor are extremely rare with poor prognosis. Only 15 cases of cardiac malignant mesenchymoma were reported in worldwide literature in 1961-1992. We report a case of primary cardiac malignant mesenchymoma in 58 year-old female patient admitted due to hemoptysis and mild exertional dyspnea.