A switching device is provided for a sewing machine for switching operation of the sewing machine from a zigzag stitching to embroidering or vice versa. The switching device comprises a rotatable disc fixedly mounted on an output shaft of a stepping motor and a sliding member that movably connects one end of a transmission rod via a pin, the other end of which is connected to a needle bar supporter or a fabric feed device, with the rotatable disc so that the one end of the transmission rod is movable between a first position on the rotatable disc which coincides with the center of rotation of the rotatable disc, and a second position on the rotatable disc which is spaced apart from the center of rotation of the rotatable disc. The switching device further comprises a stopper that engages a stub projecting from the transmission rod, in the first position of the one end of the transmission rod on the rotatable disc, and a mechanism for converting rotational movement of the stepping motor output shaft to movement of an embroidering frame in an X- or a Y-directions, dependent on whether the other end of the transmission rod is connected to the needle bar supporter or the fabric feed device, respectively, when the stopper engages the stub.