Abstract: A motor control apparatus for driving a power sewing machine comprises a main motor circuit for supplying a motor current to a DC motor from an AC power supply through a main switch and a semiconductor element with a control electrode, a controller for controlling the speed of the motor, a first control means for effecting normal stitching by controlling the conduction state of the semiconductor element, a second control means for effecting a single stitch by controlling the conduction state of the semiconductor element, and a means for switching the operation between the first and second control means. The second control means includes a needle position detector means for detecting the needle to reach predetermined positions, a switching means connected in series to the needle position detector means, a trigger voltage supply means for applying a trigger voltage to the control electrode of the semiconductor element, and a switch-operating means.