Abstract:Background: Vitamin D, also known as calciferol, is a secosteroid hormone and an essential nutrient responsible for multiple biological functions in the human body. Functionally it is different from all other fat soluble vitamins. The body can synthesis it with the help of sunlight. Objective of the Study: The specific objective of this review article is to explore the emergence of vitamin D as an important nutrient for the maintenances of optimal health and athletic performance. Acquisition of Evidence: Evidences were gathered through Pubmed searching. Studies directly matched and fulfill the primary objective of this article were considered, reviewed properly and presented systematically. Findings: Commonly Vitamin D is well recognized for its active role in calcium and phosphorous homeostasis in the human body. In recent era scientists have identified that almost every cell in the body express the vitamin D receptor, physiologically play a significant role in achieving optimal health and better athletic performance. Active from of Vitamin D plays an important role for the prevention of many chronic diseases including cancer, cardiovascular diseases, autoimmune diseases, diabetes, arthritis etc. Conclusion: Vitamin D is a potent nutrient and working as a regulator of several physiological functions in the human body. Some of these functions are well recognized but many are yet to be researched to understand the complete mechanism of action as it plays in the human body.