Primary retroperitoneal tumors are a very uncommon group of neoplasias in urology. Sixty-four primary retroperitoneal tumors admitted and treated in our hospital from january 1974 to october 2000 were reviewed retrospectively. Clinical presentation, diagnostic, treatment and evolution are analyzed. Five cases were benign (7.8%) and the remains malign (92.2%). Mesodermic tumors were the most frequent. Surgery was performed in 59 patients (92.2%). Radical resection was possible in 100% of benign tumors and 44.5% of malignant tumors. Palliative radiotherapy was performed as the only treatment in 3 patients. Two patients received only symptomatic treatment. Adjuvant chemotherapy (32 patients, 50%) and radiotherapy (19 patients, 29.6%) completed the treatment. Benign tumors 5-year global survival was 100%, malignant tumors 1-year survival was 47.4%, 3-year survival 15.2% and 5-year survival 10.1%. Mean survival was 20.15 months. As it's frequent to find an advanced neoplasm at the diagnostic, surgery must be planned with radical intention. Radiotherapy and chemotherapy could be useful in the therapeutic strategy of these tumors with poor prognosis.