Objectives: The early childhood education and care (ECEC) environment has a significant role to play in the promotion of physical activity and reduction of sedentary behaviour in young children. Educators may be an important social factor influencing children's physical activity and sedentary behaviour, however limited evidence exists on this relationship. The primary aim was to examine the relationships between educators’ and children's physical activity and sedentary behaviours within ECEC settings. Design: A cross sectional study. Methods: The study involved 11 ECEC centres from NSW, Australia (n = 110 educators; n = 490 children). Data for each centre were collected over five consecutive days. Objectively measured physical activity and sedentary behaviour were collected from children using Actigraph accelerometers and were analysed using STATA 13c. Linear regression was used to examine relationships between children and educators, adjusted for centre clustering. Results: A significant association was reported between educators’ sedentary behaviour and children's sedentary behaviour (p = 0.047). Educators spent 61% of their work day in sedentary behaviour. No significant associations were reported between educators’ physical activity and children's physical activity, for any intensity of physical activity. Conclusions: The positive relationship between educators’ sedentary behaviours and children's sedentary behaviour in this study highlights a novel area to target in future interventions. Improving physical activity and sedentary behaviours of educators will likely improve children's physical activity levels and thus health and wellbeing outcomes.