Background: The purpose of this study was to examine the relationship between organized sports participation, weight status, physical activity, screen time, and important food habits in a large nationally representative sample of Australian adolescents. Methods: Nationally representative cross-sectional study of 12,188 adolescents from 238 secondary schools aged between 12 and 17 years (14.47 ± 1.25 y, 53% male, 23% overweight/obese). Participation in organized sports, compliance with national physical activity, screen time, and fruit and vegetable consumption guidelines, and consumption of sugar-sweetened beverages and high-fat foods were self-reported. Weight status and adiposity (BMI, waist circumference) were measured. Results: Organized sports participation was higher among males and those residing in rural/remote areas. Underweight adolescents reported the lowest levels of participation. Higher levels of participation were associated with an increased likelihood of complying with national physical activity (OR = 2.07 [1.67-2.58]), screen time (OR = 1.48 [1.19-1.84]), and fruit and vegetable consumption guidelines (OR = 1.32 [1.05-1.67]). There was no association between organized sport participation and weight status, adiposity, consumption of sugar-sweetened beverages or high-fat foods. Conclusions: Participation in organized sports was associated with a greater likelihood to engage in a cluster of health behaviors, including meeting physical activity guidelines, electronic screen time recommendations, and fruit and vegetable consumption guidelines. However, participation in organized sports was not associated with unhealthy dietary behaviors including the consumption of sugar-sweetened beverages and high-fat foods. There is no association between participation in organized sports and likelihood to be overweight or obese. The role of sports in promoting healthy weight and energy balance is unclear.