The utility model provides a composite turning device for machining a circular ring face and a spherical face. The composite turning device can solve the problem that an existing machining method is big in machining difficulty, low in machining precision, unstable in machining quality and low in machining efficiency. The composite turning device comprises a box body, wherein a worm gear-worm transmission mechanism is installed in the box body. The worm gear-worm transmission mechanism comprises a worm gear and a worm, the worm is installed inside the box body in the longitudinal direction, one end of a polish rod of the worm penetrates through a lateral wall of the box body, a rotation handle is installed on the lateral end portion of the polish rod, the worm gear is installed on a worm gear shaft, the worm gear is connected with the worm gear shaft through a second key, the worm gear and the worm are in tooth engagement, the worm gear shaft is vertically installed in the box body, the lower end of the worm gear shaft is installed on a base plate of the box body, the upper end of the worm gear shaft penetrates through a top plate of the box body, the upper end of the worm gear shaft is connected with a cutterbar through a coupling mechanism, a cutter head is installed on the front end portion of the cutterbar, and a clamping body is installed on the transverse lateral wall of the box body.