We reported the clinical and pathologic features of two different types of renal mucinous tubular and spindle cell. carcinoma (MTSCC). The first patient was incidentally discovered by health examination, with lower nuclear grade, no part and distant metastasis. The second patient presented with persistence hyperpyrexia, part and distant metastasis, and high nuclear grade. Surgery were both performed successfully. The first patient had no recurrences and no distant metastases. The second patient died of multiple organ failure 3 months postoperatively. Although MTSCC is usually a low potential malignancy carcinoma, high malignancy may occur and lead to a fatal course. So it needs a proper management and prognostication.