Abstract: A direction-control device for a tennis-ball shooter having a mount plate on which two motors are mounted for driving two wheels which together control a speed and a spinning extent of a tennis ball to be served. The direction-control device includes a first bar extending along a Z-axis and drivable by a first motor to allow a pivotal movement of the mount plate on a Y-Z plane about an X-axis upon a restricted rotational movement of the first motor, thereby controlling the served tennis ball to fall in front of or behind the practicer. The device-control device further includes a second bar having a first end attached to the mount plate and a second end drivably attached to a second motor to allow a pivotal movement of the mount plate on a Z-X plane about a Y-axis upon a restricted rotational movement of the second motor, thereby controlling the spinning axis of the tennis ball to be served.