To provide a golf simulator which is individually owned by a player, has a compact and simple structure to appropriately express mathematical basics in hitting ball, and allows a general player to easily and visually perform recognition.

The golf simulator has the simple structure for visually displaying the four basic elements of input/output of an impact in golf, i.e., a vector F perpendicular to a club face, a vector F in the pass of a head, a vector P in the pass of a ball, and a surface (F-P) including the vector F and the vector P, based on their mathematical relation. Thus, a trajectory is recognized based on the impact, and also the impact is recognized based on the trajectory, so that the gold simulator is useful for obtaining the learning effect of golf technique.