Between 1992 and 1999, we treated 350 patients with skeletal metastases. A multivariable analysis of the patients was conducted using the Cox proportional hazards model. We identified five significant prognostic factors for survival, namely, the site of the primary lesion, the performance status (Eastern Cooperative Oncology Group status 3 or 4), the presence of visceral or cerebral metastases, any previous chemotherapy, and multiple skeletal metastases. The score for each significant factor was derived from the corresponding estimated regression coefficients (natural logarithm of the hazard ratio). The prognostic score was calculated by adding all the scores for individual factors. The rate of survival was 31% at six months and 11% at one year for the patients with a prognostic score of 6 or more. By contrast, patients with a prognostic score of 2 or less had a rate of survival of 98% at six months and 89% at one year. This scoring system can be used to determine the optimal treatment for patients with pathological fractures or epidural compression.