Current prognostic factors often fail to predict the patients outcome in localized renal cell carcinoma. In this study we evaluate microvessel density (MVD), a parameter of angiogenesis, as a prognostic factor in localized, clear cell renal cell carcinoma. The clinical and histological records of 61 patients were reviewed, who were treated with radical nephrektomy between 1991 and 1995. The microvessel density was meassured by immunohistochemical staining with CD 31 monoclonal antibody and counted by manual and computerized image analysis. Microvessel density was higher in low as compared with high grade tumors. Comuterized image analysis showed a lower vacularization in pT2 than in pT1a and pT1b tumors. In cases with synchronous metastases the number of microvessels was lower than in those with metachronous or no evidence of metastases. Patients with good vascularized tumors, who developed metastases, had a better progression free and overall survival. There was only little difference in 5-year survival rates of patients with renal cell carcinomas with high vascular density and low vascular density. Otherwise patients with good vascularized tumors lived longer within these 5 years, than those with poor vascularized tumors. These data suggest, that low microvessel density could be more favourable for patients outcome. However, microvessel density was not a prognostic factor for localized, clear cell, renal cell carcinoma.