Objective: For MSCC treatment, a short treatment time is desirable, especially if survival prognosis is poor. Survival depends on the primary tumor, extent of disease, performance status, ambulatory status, and the number of involved vertebrae. These factors may help to define the appropriate regimen for the individual patient. Our study compares short-course (1 × 8 Gy, 5 × 4 Gy) and long-course RT (10 × 3 Gy, 15 × 2.5 Gy, 20 × 2 Gy) for functional outcome in MSCC patients with renal cell carcinoma. Methods: The following potential prognostic factors for functional outcome were retrospectively investigated: age, performance status, involved vertebra, ambulatory status, time of developing motor deficits before RT, radiation schedule (short-course RT, n = 37; long-course RT, n = 50). Results: Eighty-seven patients were included in this retrospective study, 25 patients (29%) showed improvement of motor function, 52 patients (60%) no change, 10 patients (11%) deterioration. 25% of non-ambulatory patients became ambulatory after RT. Functional outcome was affected by the time of developing motor deficits before RT (p < 0.001). The RT schedule had no significant impact (p = 0.91). In the short-course RT sub-group, functional outcome was similar for 1 × 8 Gy and 5 × 4 Gy (p = 0.99). Conclusion: Short-course and long-course RT appear similarly active for MSCC in patients with renal cell carcinoma. Short-course RT appears preferable, as it is means less patient discomfort. Because 1 × 8 Gy and 5 × 4 Gy were comparably effective, 1 × 8 Gy may be suggested the best actual choice.