A shutter apparatus of a cash transaction machine, including: a drive unit; a cam rotating body engaged with the drive unit and including a guide rail eccentric to the rotation center thereof; and a shutter including a guide projection moving along the guide rail, which shuffles a straight path in response to the rotation of the cam rotating body. Since the shutter can be moved by using the rotation of the cam rotating body, the structure of the shutter apparatus can be simply maintained. Also, the rotation center of the cam rotating body and the guide projection are located on one straight line, thereby forming a structural lock without an additional locking unit.