Methods: We aimed to investigate the correlation between the incidence of vitamin D receptor (VDR) gene polymorphisms (rs11568820, rs10735810, rs1544410, rs7975232, and rs731236, commonly described as Cdx2, FokI, Bsm, ApaI, and TaqI, respectively) and vitamin D concentration with the clinical course of IBD (disease activity, extent of the intestinal lesions). This evidence concerns the gene VDR and inflammatory bowel disease.