Prostate cancer is the second leading cause of cancer death among men in developed countries. Estrogen receptor-alpha (ER-α), vitamin D receptor (VDR), and the calcium-sensing receptor (CaSR), partly through their effects on calcium levels are implicated in the proliferation and carcinogenesis in the prostate gland. VDR, ER-α and CaSR genes show polymorphisms in humans that appear to have clinical significance in many pathological conditions, such as prostate cancer. Our aim was to evaluate the role of ER-α (PvuII, XbaI), VDR (BsmI) and CaSR (A986S) gene polymorphisms and serum calcium levels in the pathogenesis of prostate cancer.Two hundred four patients with prostate cancer and 102 healthy controls were recruited into a hospital-based case control study. After genotyping, the relationship between the individual genotypes and prostate cancer was investigated.Both the ER-α XbaI and the VDR BsmI polymorphisms were significantly related to the risk of prostate cancer. An age adjusted logistic regression limited to controls and patients not receiving bisphosphonate therapy showed that higher corrected serum calcium and the VDR Bb/BB genotypes independently increased the risk of prostate cancer.ER-α XbaI and VDR BsmI genetic polymorphisms had a significant association with the risk of prostate cancer. Both VDR BsmI genotypes and serum calcium levels were independently related to the risk of prostate cancer, suggesting an influence of VDR on the development of this malignancy.