Childhood obesity is a global epidemic. Health videogames are an emerging intervention strategy to combat childhood obesity. This systematic review examined published research on the effect of health videogames on childhood obesity. Fourteen articles examining 28 health videogames published between 2005 and 2013 in English were selected from 2433 articles identified through five major search engines. Results indicated that academic interest in using health videogames for childhood obesity prevention has increased during this time. Most games were commercially available. Most studies were of short duration. Diverse player and game play patterns have been identified. Most studies involved players of both genders with slightly more boys. The majority of players were non-white. Most studies had the players play the games at home, whereas some extended the play setting to school and sports/recreational facilities. Most of the games were commercially available. Positive outcomes related to obesity were observed in about 40 percent of the studies, all of which targeted overweight or obese participants.