The purpose of this study was to grasp the actual state of amounts of physical activity and fundamental movement in free play on the playground, as well as characteristics of fundamental movement based on differences in amounts of physical activity, with 53 4-year-olds (24 boys, 29 girls) as the target. The following points became clear: 1) In free play on the playground, there was a gender-based difference in the amount of physical activity, as boys took 2533.2±538.2 steps with an MVPA of 17.9±5.1 minutes, and girls took 1866.0±811.8 steps with an MVPA of 14.2±6.0 minutes. 2) Depending on the amount of physical activity, there was a significant difference in girls’ manipulative movements as to the number of types of fundamental movement exhibited. 3) It became clear that the content of play differed depending on the amount of physical activity, and that fundamental movement experienced differed accordingly. 4) It was confirmed that regardless of the state of physical activity, there was movement that was either not exhibited or had a low rate of exhibition. From the above, while free play on the playground is important for the physical activity of young children, and there was no difference in the number of fundamental movements exhibited depending on the amount of physical activity, because the fundamental movement and content of play that were experienced differed, continued support based on the characteristics of young children’s physical activity is considered to be necessary.