Injury of posterolateral corner is unusual, but it can cause disability due to severe instability and cartilage damage. However, the anatomical structures, diagnosis and treatment have not defined clearly yet. Posterolateral corner injury is regarded as the one of main factor to the results of failure in cruciate ligament reconstcution if it was undiagnosed and untreated. Diagnosis of postetolateral corner injury is consists of physical exam, radiographic finding, MRI, and arthroscopic findings. The treatment method of of postetolateral corner injury depends on the time and severity of injury. Anatomical reconstruction of posterolateral corner shows the better clinical outcome than non anatomical reconstructions, but the clinical results of long term follow up is still needed. Therefore, the aim of this article is to review the recent literatures and to organize diagnosis and treatment of posterolateral corner injury.