Activating mutations in the cytosolic serine/threonine kinase, BRAF, have been reported in a variety of neoplasms. BRAF activation may contribute to tumor growth via activation of the MAP/ERK kinase pathway, and BRAF represents a possible therapeutic target. Activating BRAF mutations were recently reported in approximately 10% of prostate cancer cases in Asian patients. In the present study, 43 hormone refractory prostate cancers were analyzed for BRAF mutations in order to determine whether anti-BRAF therapy is a suitable approach for advanced prostate cancer patients. In all of the studied tumors, BRAF exons 11 and 15 were PCR-amplified and sequenced, including the backward and forward sequences. BRAF mutations were noted only in the positive control tissues, but were not found in any of the 43 analyzed prostate cancers. We conclude that BRAF mutations occur only rarely in prostate cancers in Caucasian patients and are not associated with tumor progression. The application of anti-BRAF therapies may therefore not be beneficial for prostate cancer.