Purpose: This paper aims to describe Australian children's perceptions of healthiness and sources of health knowledge in order to develop an understanding of young children's perceptions, knowledge and sources of influence to guide future behaviour change and health promotion strategies. Design/methodology/approach: One-hour interactive focus groups were conducted in a South Australian primary school. Four small groups (n = 28) of children aged five to nine participated in focus groups in which they were asked to discuss being healthy and their sources of health information as well as engaging in storying around the healthy or unhealthy behaviours of fictional characters. Findings: Children generally perceived themselves to be healthy. Perceptions of healthiness were equated with performing positive dietary (primarily eating fruit) and physical activity behaviours. Behaviours on an unhealthy day related to being sedentary and consuming "junk foods". Commonly cited sources of health information included family members, teachers and public health campaigns. Practical implications: Understanding how young children perceive health behaviour and how to deliver health education appropriately to children (including who delivers these programs) could improve the efficacy of future programs targeting this group. This study offers insight into junior primary children's perceptions of healthy diet and activity behaviours and can assist in the improvement of future health interventions and programs. Originality/value: Existing research on how younger children perceive healthiness is limited. The methods used in this study allowed the authors to explore these perceptions in a way that limited how much the topics of the conversation were predetermined. (Contains 2 tables, 1 figure, and 3 notes.)