BACKGROUND: Injuries due to sports and activity amongst young children constitute a significant public health burden. It is important to quantify this risk to ensure that the benefits of sport participation are not outweighed by the potential harms. AIM: to summarise the literature reporting exposure based injury rates for various forms of physical activity amongst children younger aged 15 years and younger METHODS: a systematic review was conducted including all studies that reported injury rates per exposure measure for children younger than 16 years of age. RESULTS: We located 34 studies that met the inclusion criteria of which 19 reported injury rates per an hourly based exposure measured and 15 reported injury rates according to some other measure. The included studies covered 13 different sports and activities, mostly team ball sports with soccer being the most widely studied activity. The injury definition and method of ascertaining and measuring injuries differed between studies which created a large variation in reported injury rates that did not necessarily represent actual injury risk differences between activities. The highest hourly based injury rates were reported for ice hockey and the lowest were for soccer, although the range of injury rates for both of these activities were wide. CONCLUSION: There exists a significant body of literature reporting injury rates for childhood sports, however there are large inconsistencies in injury definition and study methods. Very few studies have studied sports related injuries in children younger that 8 years or in non-organised sports paradigms.