Vitamin D is a fat-soluble lipophilic prohormone. Vitamin D is synthesized in human body inresponse to UV light. The significance of vitamin D have been documented in a large number of experimental researches that support relationship between vitamin D status and human health. The chief identified impacts of vitamin D on human body is bone health, pregnant women health, foetal health, mineral homeostasis, anti-inflammatory etc. Aim of the present review is to summarize the impact of maternal vitamin D supplementation on maternal-fetal outcomes, to identify the most commonly used tools for measuring maternal vitamin D supplementation, and report on the maternal and foetal outcomes of maternal vitamin D supplementation. The deficiency of Vitamin D in pregnant women and neonates is a common problem that affects people all over the world. The preterm birth risk is increased by 60% in pregnant mothers when the maternal 25-OH-D concentration is less than 40 µg/ml. The research articles consider for the present systemic review meet the following criteria: (i) A non-intervention, intervention and quantitative research studies to look at the effects of maternal vitamin D supplementation on maternal and foetal outcomes, and (ii) the article was published in peer-reviewed journals.