Aim: This study examined adolescent nutrition behaviours and associations with a range of adolescent and parent characteristics to underpin the development of key objectives for focus in the development of school-based interventions for the prevention of adolescent overweight/obesity. Methods: Three hundred and sixty-two adolescents from six secondary schools, completed questionnaires regarding their nutrition behaviours, physical activity and sedentary activities, and 349 parents completed questionnaires to report their height and body weight, nutrition behaviours, physical activity, and values of adolescent obesity related behaviours. Adolescent height and body weight were objectively measured for calculation of body mass index. Logistic regression (P<0.05) and Pearson chi-square analyses of 295 matched adolescent and parent questionnaires were conducted to examine associations. Results: Adolescent healthy nutrition behaviours were negatively associated with time spent in small screen recreation (odds ratios 0.48, P=0.02), and positively associated with time spent in sedentary education (odds ratios 2.44, P=0.004) and physical activity (odds ratios 2.53, P=0.03). Gender differences were found. No associations were found between adolescent healthy nutrition behaviours and adolescent body mass index, adolescent physical activity, parent body mass index, parent nutrition behaviours, physical activity or parent values of adolescent health behaviors. Conclusions: Interventions to promote adolescent healthy nutrition behaviours should be gender specific and include action around a range of obesity-related health behaviours including physical activity and time spent in small screen recreation.