Objective: During the early years, parents have a major influence on children's diets and developing food choices. We investigated parenting styles as predictors of 2-5-year-old children's diets and whether general nutrition knowledge (GNK) mediated these influences. Design: Cross-sectional research. Questionnaires measured demographic and lifestyle variables, family environment, parenting styles and feeding practices, child diet and GNK. Regression models tested GNK as a mediator of relationships between parenting variables and child diet (fruit/vegetable and non-core food consumption), controlling for confounders and family environment. Setting: Questionnaires were completed by main caregivers at home. Subjects: Parents of children aged 2-5 years (n 269). Results: Higher child fruit/vegetable consumption was associated with lower overreactive parenting and restriction, higher authoritative parenting and dining together as a family; with lax parenting approaching statistical significance (P 5 0?083) and 19 % of variance explained by the model. GNK was not a significant predictor. Conversely, non-core food consumption was associated with higher over-reactive and lax parenting as well as child age, increased takeaway food consumption and higher television viewing; GNK had a small effect (P 5 0?043) and 28 % of variance was explained by the model. GNK was a significant mediator only for authoritative parenting on non-core food (effect 5 20?005). Conclusions: These findings highlight that young children's diets may be improved by interventions targeting a range of positive and supportive parenting practices in conjunction with nutrition knowledge education for parents of young children. Further insights will come from closer attention to the nature and role of restrictive feeding practices v. laxness and longitudinal research.