Abstract: This study explored the relationship among theory of mind (ToM), cooperative behavior and Machiavellianism in primary school children. The methods included several ToM tasks (such as the faux pas understanding tasks, the white lie tasks and the story comprehension tasks), a cooperative behavior task and Kiddie Mach. 90 primary school children from grade 2, 4 and 6 were involved. The result indicates: (1) There exists a significantly positive correlation between children’s ToM and their cooperative behavior. The degree of ToM can forecast that of cooperative behavior. (2) Children’s ToM is not significantly related to their Machiavellianism. (3) There is a significantly negative correlation between children’s cooperative behavior and their Machiavellianism. The degree of high Machiavellianism group’s cooperative behavior is much lower than that of low Machiavellianism group.

Key words: theory of mind, cooperative behavior, Machiavellianism, relationship, primary school children