A zigzag sewing machine for sewing fabric, comprises, a sewing machine housing which has a base portion which underlies an upper arm portion which is supported on a column extending upwardly from the base portion. A needle bar pendulum is mounted in the upper arm for swinging back and forth motion and a needle bar is mounted therein for upward and downward motion. A feed mechanism is located in the base portion below the upper arm and it includes a movable fabric support which is engageable with the workpiece to move it selectively in either a forward or backward direction. The drive mechanism for driving the feed mechanism and for controlling the swinging movement of the needle bar is contained in the base portion and it is operated under the control of a plurality of control cams by an operating element which is moved by depressing a key in a wall of the base portion so as to vary the type of stitch pattern which is effected.