Traumatic dental injury (TDI) in children and adolescents has become one of the most serious problems in public health. TDI has relatively high prevalence, broad etiology, which may influence esthetic and function of involved teeth, resulting in economic loss and affecting life quality. The prevalence of TDI increases with children's age. Males suffer from TDI more easily than females. Maxillary central incisors are most commonly affected. Luxation and enamel fracture are common types of TDI. The main causes of TDI include fall, collision, sport, violence and accident. Overjet, lip incompetency and caries may be risk factors of TDI. According to risk factors of TDI, appropriate prevention measures need to be taken, which is the key of preventing TDI.