Background: It is important to understand the correlates of physical activity (PA) to influence policy and create environments that promote PA among preschool children. We compared preschoolers’ PA in Swedish and in US settings and objectively examined differences boys’ and girls’ indoor and outdoor PA regarding different intensity levels and sedentary behavior.Methods: Accelerometer determined PA in 50 children with mean age 52 months, (range 40–67) was recorded during preschool time for 5 consecutive weekdays at 4 sites. The children wore an Actigraph GTIM Monitor.Results: Raleigh preschool children, opposite to Malmö preschoolers spent significantly more time indoors than outdoors (P < .001). Significantly more moderate-to-vigorous intensity physical activity (MVPA) was observed outdoors (P < .001) in both settings. Malmö children accumulated significantly more counts/min indoors (P < .001). The percent of MVPA during outdoor time did not differ between children at Raleigh and Malmö.Conclusion: Physical activity counts/minutes was significantly higher outdoors vs. indoors in both Malmö and Raleigh. Malmö preschoolers spent 47% of attendance time outdoors compared with 18% for Raleigh preschoolers which could have influenced the difference in preschool activity between the 2 countries. Time spent in MVPA at preschool was very limited and predominantly adopted outdoors.