Nickan Research Institute Journal of Parathyroid Disease 2345-6558 4 1 2016 01 01 Vitamin D and chronic kidney disease 25 30 EN Fatemeh Hayati Mohammad Amin Nasouti Shokhouh Shayanpour Shahla Ahmadi Halili Hossain Karimpourian Zarrin Beladi Mousavi Journal Article Prevalence of hypovitaminosis D is increasing in the world especially among poor countries and it has many varieties of manifestation and disease including rickets in children and osteomalacia and osteoporosis in adult. It also can affect on functional of some organ like renal and cardiovascular system and even has effect on mortality rate of some of these patients. Inadequate vitamin D in food regimen is one of reasons of hypovitaminosis D. The production of active form of this vitamin mainly is located in kidney cells, therefore end-stage renal disease (ESRD) patients or patients who have chronic kidney disease (CKD), have high chance for low serum level of the active form of this vitamin. Secondary hyperparathyroidism and renal osteodystrophy which are important side effect of CKD, be happen because of deficiency and defect in absorption of this vitamin. According to rapid increase in the prevalence of hypovitaminosis D, the aim of this review article is to summarize some of investigation about hypovitaminosis D especially among patients who have CKD.