<p>This study aimed to examine the association of walking to school with physical activity and physical fitness in children. A total of 249 children (mean age: 9.7 ± 1.2 were assessed for mode and time of school commute, physical activity, and physical fitness. Physical activity was assessed using an accelerometer to measure step counts, sedentary time, light physical activity, and moderate-to-vigorous physical activity (MVPA). Physical fitness was measured using eight tests: hand grip, sit-ups, sit and reach, side-to-side steps, 20-m shuttle run, 50-m dash, standing broad jump and softball throwing.</p><p>The percentages of students walking to and from school were 89.6% and 75.1%, respectively. For both boys and girls, differences in step counts and MVPA before and after school and the entire day were observed between groups with short and long walking times to school. In girls only, longer walking to school was partially associated with higher physical fitness in the side-to-side jump, 20&#xa0;m shuttle run, standing broad jump and total score. These findings indicate that walking to and from school is associated with higher levels of physical activity. Although the association with physical fitness was less clear than that with physical activity, walking to school may be more strongly related to physical fitness in girls than in boys. While these results may not be generalizable to boys or to all children in Japan, this study provides evidence supporting the promotion of walking as a mode of transportation to and from school to increase physical activity levels.</p>