The aim of this study was to investigate the epidemiology of crossfit sport injuries in Tehran gyms. This research was descriptive and retrospective studies. Men and women participating in crossfit training in Tehran gyms were studied. Data were analyzed using SPSS software version 18 and Chi-square test (X2) at a significance level of 0.05. The results showed that the incidence of injury per 1000 hours of training in men and women was equal to 4.421 and 5.336, respectively, and the most common areas of injury in men and women were shoulder and knee. In men, 22% and in women, 29.7% of the injuries was strain. According to the findings, which indicate the high prevalence of crossfit injuries, the medical staff of teams, coaches and athletes in this field are advised to take the necessary measures to consider the potential risk factors associated with the occurrence of injuries to prevent them.