Abstract: Objective To explore the relationship between training injuries and core strength training time in the 400-meter obstacle course,and analyze the possible influencing factors of training injuries. Methods Data were collected from 207 military school students,including height,waist circumference,weight and BMI,training injury history and core strength training in the past six months by questionnaire survey.Then the students took part in the two-month 400-meter obstacle course from March to April in 2018.The binary logistic regression analysis was applied to analyze the relationship between training injury history,waist circumference,BMI during training and the occurrence of 400-meter obstacle training injury. Results A total of 63 cases of training injuries from 59 students (30.41%) occurred during the two-month 400-meter obstacle training,including 5 cases of upper limb injury (7.94%),55 cases of lower extremity injury (87.30%),and 3 cases of trunk injury (4.76%).Training injury was more likely to occur in students with a history of injury (52.54% vs 22.22%,P=0.000),and the students who paticipated less core strength training (<4 h vs ≥4 h:2.65% vs 23.81%,P=0.009).Logistic regression showed that the risk of training injury increased 1.259 times with the increase of every one unit of BMI index;Training less than 4 hours (OR,3.488;95% CI,1.766 to 6.889) and history of sports injury (OR,2.369;95% CI,1.204 to 4.661) increased the risk of injury in 400-meter obstacle training. Conclusion At least 4 hours of core strength training per week and BMI control will help to reduce the risk of training injuries in 400m obstacle training.