Bone metabolism requires a balance mechanism between intricate processes of bone formation and resorption, which is affected by the essential interaction between osteoblasts and osteoclasts. Interleukin-17 (IL-17) is a family of cytokines consisting of six isoforms: IL-17A, IL-17B, IL-17C, IL-17D, IL-17E, and IL-17F. Among these isoforms, IL-17A has shown promising and novel roles in the regulation of bone metabolism. IL-17A has also captivated the interest of many researchers since its discovery because of its role as a pro-inflammatory cytokine which mediates a few inflammatory processes. This review describes the biology of IL-17A and its receptor as well as summarises the regulatory role of IL-17A in bone metabolism and diseases through some known pathways. Understanding the function of IL-17A in bone metabolism may lead to the development of therapeutics or diagnostic strategies for some bone diseases; as well as future therapy using tissue engineering and regenerative medicine approaches.