Objective: This study aimed to investigate the prevalence of mouthguard used and orofacial trauma in a roller hockey population and verify the several associated factors. Materials and Methods: An observational cross-sectional study based on clinical observation and questionnaire application to the athletes under search. The sample consisted of 117 roller hockey athletes between 13 and 19 years old, in Portugal, in several clubs which were, Sporting Clube de Portugal, Sport Lisboa e Benfica, Clube Desportivo de Paço de Arcos and Parede Futebol Clube. Results: The prevalence of mouthguard used was 16.2%, and 56.2% of them used Type II, and 47.4% Type III. The prevalence of orofacial trauma was 38.5%, in which 71.1% of these dental injuries involved the upper incisors, which were the most affected teeth, both the deciduous and definitive dentition. At the time of injury, only four athletes wore mouthguards, which 1 type I, 2 of type II and 1 of model III. Conclusion: Roller hockey is a sport in which the prevalence of mouthguard use is low, and that of orofacial trauma is high. Thus, the mouthguard is a device that should be more used by athletes, since it is useful in preventing these injuries.