Purposes: Evaluate the prevalance of dental trauma in patients who treated in Ha Noi National hospital of Odonto-Stomatology. Materials and methods: the data is collected from medical records of patients who are addmitted in national hospital of ondonto-stomatology since 1/2009 to 6/2013. Results: Prevalence of TDIs was found to be 9,9 percent of patiens came hospital by reasons of trauma. A total of 716 patients with 1287 traumatized teeth, males (443 cases, 61,9 percent) and females (273 cases, 38,1 percent). 77,3 percent of the injuries were to the maxillary anterior teeth. Maxillary central incisor was the most common tooth to be affected due to trauma. The most frequent type of injury was subluxation (29,3 percent), enamel-dentin crown fracture without pulpal exposure (26,0 percent), and avulsion (17,8 percent).The most common cause of dental traumawas traffic accident (47,1 percent).