Understanding the osteoarthritis (OA) disease process will contribute to the development of treatment options that target changes at the molecular level that occur early in this disease. Platelet-rich plasma (PRP) targets changes at the molecular level that occur as a result of anabolic and catabolic processes in osteoarthritis of the knee. Platelet-rich plasma is rich in autologous growth factors. It is one of the simple, low-cost, and minimally invasive treatment methods in which a natural concentration of bioactive molecules is obtained. Molecules that play a role in the natural healing process are locally given to the healing area in high amounts, increasing the body`s natural healing process in the injury area. Thus, it is aimed to accelerate the functional recovery process. This article aims to review the PRP treatment, which is applied as an alternative treatment option in patients with knee OA, under the guidance of the literature with a high level of scientific evidence.