A motion generation device may be for generating a movement for changing the robot from a first orientation to a second orientation, and include a first acquisition unit that acquires first orientation information that specifies the first orientation and second orientation information that specifies the second orientation, a second acquisition unit that acquires at least one priority item regarding the movement for changing from the first orientation to the second orientation, and a movement generation unit that generates a motion of the robot that includes a movement path along which the robot moves from the first orientation to the second orientation, based on the first orientation information, the second orientation information, and the priority item that were acquired.