The piriformis syndrome is an uncommon nerve entrapment syndrome which is characterized by sciatica. The causing of syndrome can be related to anatomic variations of sciatic nerve, piriformis muscle and their incompatible neighboring during trajectory. The next reason is traumatic injury of the piriformis musle. The main symptoms are hip pain, leg pain was increased by internal rotation of the leg and sciatica pain was provoked by palpation of nerve (tinnel finding). Etiology is variable and path-physiology was not fully understood. Approximately, 50% of the cases have a trauma anamnesis. The first lie treatment is conservative methods and then local injections and surgical treatment can be used by step by step. This article reviews the pathophysiology and management of piriformis syndrome.