The use of magnetic resonance imaging (MRI) for diagnosis and preoperative staging of renal cell carcinoma was evaluated in 79 patients with 88 tumors. Gradient-echo and spin-echo images before and after intravenous administration of Gadolinium-DTPA were compared with the results of computed tomography (CT) and histologic staging. The two imaging techniques had comparable results: T-stage was predicted correctly with CT in 78.4% and with MRI in 84.0% of the cases, while the N-stage was accurately assessed in 81.8% and 79.5%, respectively. MRI had some advantages in diagnosing perirenal tumor spread and in excluding an infiltration beyond Gerota's fascia. Therefore, MRI is a true alternative to CT for staging large renal cell carcinomas and especially for patients with contraindications for iodinated contrast agents.