As the main stabilizing structure of the medial ankle joint, deltoid ligament plays a role in counteracting excessive eversion of the hindfoot and external rotation of the talus during ankle movement so as to maintain the biomechanical stability of ankle joint. Although the incidence of deltoid ligament injury is low, improper diagnosis and treatment can affect the path of talus motion and eventually lead to chronic medial instability or traumatic arthritis of the ankle joint, seriously affecting the normal life and motor function of the patients. The diagnosis of deltoid ligament injury needs to be based on the characteristics of the injury, physical examination and imaging, among which X-ray, MRI and ultrasonography are most frequently used. There are various methods to treat deltoid ligament injury according to the type of injury, and thus the choice of treatment has been a hot topic in the field of foot and ankle surgery. The choice of non-surgical or surgical treatment for acute deltoid ligament injury remains controversial. For the treatment of chronic deltoid ligament injury, there is no consensus on direct repair or deltoid ligament reconstruction. In addition, the choice of autologous or allograft tendon or wire anchors for deltoid ligament reconstruction is also disputed. The rehabilitation of deltoid ligament injury is crucial to the early restoration of motor function of the ankle joint, but the related guidelines or consensus are scarce. In order to fully understand the characteristics of deltoid ligament injury, make accurate diagnosis and formulate reasonable treatment and rehabilitation programs, the authors review the research progress in deltoid ligament injury from aspects of anatomical characteristics, biomechanical mechanism of injury, diagnosis, treatment and postoperative functional rehabilitation, hoping to provide a reference for the clinical diagnosis and treatment of deltoid ligament injury.