AbstractBackgroundSome studies have revealed that a substantial proportion of the younger population has engaged in problematic gaming with even infants recently being able to enjoy video games. However, the relationship between the risk for problematic gaming and age at which habitual gaming starts remains unknown. This study therefore investigated this relationship among adolescents.MethodsA survey was conducted at eight public junior high schools across Japan. The questionnaire included items regarding the background, night‐time sleep, age at which weekly gaming began, time spent on the Internet and gaming, the Japanese version of Young’s Diagnostic Questionnaire, the Ten‐Item Internet Gaming Disorder Test (IGDT‐10), and others. We analyzed 549 participants who engaged in weekly gaming and have played games during the past year.ResultsAmong the participants, 1.8% were suspected to have Internet gaming disorder (IGDT‐10 ≥ 5). Bedtime and wake‐up time on weekdays and holidays were significantly later among problematic gamers (IGDT‐10 ≥ 3) than among normal gamers (IGDT‐10 ≤ 2). Onset of weekly gaming before the age of 5 was associated with a significantly higher risk of problematic gaming than onset of weekly gaming after the age of 10.ConclusionsOur results revealed that the risk for problematic gaming was positively associated with a younger age at which weekly gaming begins. Longitudinal problematic gaming prevention, starting from an early stage, is thus necessary.