Introduction: The benefits of regular physical activity for children are significant. Previous research has addressed the quantity and quality of children's physical activity while in early childhood education and care (ECEC) settings, yet little research has investigated the social and physical environmental influences on physical activity in these settings. The outcomes of this study will be to measure these social and physical environmental influences on children's physical activity using a combination of a real-time location system (RTLS) (a closed system that tracks the location of movement of participants via readers and tags), accelerometry and direct observation. Methods and analysis: This study is the first of its kind to combine RTLSs and accelerometer data in ECEC settings. It is a cross-sectional study involving ∼100 educators and 500 children from 11 ECEC settings in the Illawarra region of New South Wales, Australia. A RTLS and Actigraph GT3X+ accelerometers will be concurrently used to measure the level and location of the children's and educators' physical activity while in outside environments. Children and educators will wear accelerometers on their hip that record triaxial acceleration data at 100 Hz. Children and educators will also wear a tag watch on their wrist that transmits a signal to anchors of the RTLS and the triangulation of signals will identify their specific location. In addition to these, up to three random periods (10-25 min in length) will be used to collect observational data each day and assessed with the classroom assessment and scoring system to measure the quality of interactions. In conjunction with the real-time location system (RTLS) and accelerometers, these observations will measure the relationship between the quality of interactions and children's physical activity. Ethics and dissemination: The results of this study will be disseminated through peer-reviewed publications and presentations. Ethical approval was obtained through the University of Wollongong Human Research Ethics Committee (HE14/330).