We performed a prospective study to evaluate injury patterns in a large population of high school wrestlers during one season. Preseason screening was performed on 458 male wrestlers from 14 different high schools. Certified athletic trainers submitted detailed weekly team and individual injury reports. There were 219 injuries in 418 wrestlers followed throughout the season for an overall injury incidence of 52 injuries per 100 wrestlers per season and an injury rate of 6.0 injuries per 1,000 exposures. The most commonly injured areas were the shoulder (24%) and knee (17%). Injured wrestlers were an average of 5 months older and had a 32% higher experience level than noninjured wrestlers. Wrestlers with ligamentous laxity suffered fewer shoulder injuries than the other wrestlers. The majority of injuries occurred in practice (63%), although the injury rate was higher in match competitions. Sixty-eight percent of practice injuries occurred during hard wrestling, 23% during drills, and 9% during conditioning. The most common wrestling situation resulting in injury was the takedown position (68%). Our results show that the older and more experienced wrestler may be at greater risk of injury. Hard wrestling during practice and the takedown position resulted in the highest occurrence of injury.