A 45-year-old man felt sudden pain in the left abdomen while taking a bath. Computed tomography (CT) showed a huge hematoma above the left kidney, which was diagnosed as spontaneous rupture of the kidney. Two months later, several low-density areas were observed in the liver on CT. Suspecting renal cell carcinoma (RCC) with multiple liver metastasis, we performed left radical nephrectomy and partial hepatectomy. A pathological study revealed a small RCC of 2 cm in diameter in the middle of the left kidney. In spontaneous renal rupture secondary to renal tumors, imaging studies such as CT or MRI sometimes fail to demonstrate primary lesions.