In this study, the relationship between adolescent leisure and gambling was explored. Three different models of time usage were compared as potential predictors of gambling behaviour and problem gambling among 769 adolescents (15 to 18 years old) from five secondary schools in Melbourne. More leisure time, particularly unstructured leisure, predicted more frequent gambling behaviour for girls and boys. Specific activity factors provided the best time usage-based prediction of gambling behaviour. More time socialising and being involved in organised sport predicted more gambling for boys, possibly because of the access these activities provide to gambling venues. For boys, lower levels of so-called masculine pursuits (activities with other male peers) were associated with problem gambling, as were “cognitive pursuits” such as board games and collecting hobbies. For girls, more time in studious activity mitigated against gambling frequency. Lower levels of typically “feminine” adolescent pursuits predicted problem gambling. By far the major predictor of problem gambling for both sexes was gambling frequency. The role of leisure in problem gambling was discussed in terms of the role played by peer socialising, which may increase risk through access to gambling venues yet simultaneously increase protection through a sense of belongingness.