A behavior control system is capable of causing an agent carry out a task by smooth motions. The behavior control system makes it possible to reproduce a typical shape characteristic of a reference trajectory, i.e., the characteristic of a motion of an instructor carrying out a task, by using a first model defined on the basis of a plurality of reference trajectories representing the position of a first state variable in a time-series manner. Further, a learning trajectory representing the position of a second state variable in a time-series manner is generated on the basis of a second model, which represents an agent's motion in which the position of the second state variable corresponding to the first state variable and one or a plurality of time differential values (a displacing velocity and acceleration) thereof continuously change, in addition to the first model.