Primary cardiac tumors of the mitral valve are extremely rare; however. they present a major risk of embolization. Therefore, prompt diagnosis and urgent treatment is obligatory. The authors report the case of a 60-year-old man with a huge mitral valve mass and its vascularity, which was diagnosed by transthoracic echocardiography and selective coronary arteriography. Our patient's mitral valve tumor had a size of 5.9 X 2.9 cm, which was the largest size reported up to this time in this location. The patient died from a major cerebrovascular event before surgical excision could be performed.