Renal cell carcinoma (RCC) is the most frequent urological malignant tumor in adults and it occurs mostly between the fifth and the sixth decades of life. The male-female ratio is 3:1 and it is more common in smokers. It accounts for approximately 3% of adult malignancies; 90~95% of neoplasms of the kidney. The classic triad of presenting symptoms of RCC is hematuria, back pain and a mass in the flank. More than 50% of RCCs show metastasis to breast, lung and regional lymph nodes, and 15% present in the orofacialmaxillary region. This case is about a 66 year-old man who was treated for painless swelling in the left masseteric area. The mass was surgically excised and sent for biopsy. It was diagnosed as RCC and two weeks later nephronectomy of the left kidney was performed. Metastasis to other organs was detected and the patient received radiation therapy. In this case we were able to find the primary lesion by the metastatic lesion.