Children’s learning about food is considerable during their formative years, with parental influence being pivotal. Research has focused predominantly on maternal influences, with little known about the relationships between fathers’ and children’s diets. Greater understanding of this relationship is necessary for the design of appropriate interventions. The aim of this study was to investigate the associations between the diets of fathers and their children and the moderating effects of fathers’ BMI, education and age on these associations. The diets of fathers and their first-born children (n 317) in the Melbourne Infant Feeding Activity and Nutrition Trial (InFANT) Program were assessed using an FFQ and 3×24-h recalls, respectively. The InFANT Program is a cluster-randomised controlled trial in the setting of first-time parents groups in Victoria, Australia. Associations between father and child fruit, vegetable, non-core food and non-core drink intakes were assessed using linear regression. The extent to which these associations were mediated by maternal intake was tested. Moderation of associations by paternal BMI, education and age was assessed. Positive associations were found between fathers’ and children’s intake of fruit, sweet snacks and take-away foods. Paternal BMI, education and age moderated the relationships found for the intakes of fruit (BMI), vegetables (age), savoury snacks (BMI and education) and take-away foods (BMI and education). Our findings suggest that associations exist at a young age and are moderated by paternal BMI, education and age. This study highlights the importance of fathers in modelling healthy diets for their children.