Vitamin D has antiproliferative, antiangiogenic, and apoptotic properties. There is some evidence supporting an association between vitamin D-related gene variants and prostate cancer risk. We report results from this population-based case-control study of genes encoding for the vitamin D receptor (VDR), the vitamin D activating enzyme 1-alpha-hydroxylase (CYP27B1), and deactivating enzyme 24-hydroxylase (CYP24A1). Forty-eight tagging single nucleotide polymorphisms (tagSNP) were analyzed in 827 incident prostate cancer cases diagnosed from 2002 to 2005, and in 787 age-matched controls. Contrary to some earlier studies, we found no strong evidence of altered risk of developing prostate cancer overall or within clinical measures of tumor aggressiveness for any of the tagSNPs when they were assessed individually or in haplotypes