The invention relates to worm-gear speed-reducing wire-feeding motor equipment as well as a wire feeding device provided with the same and a welding system provided with the same. The wire-feeding motor equipment comprises a motor, a power output shaft and a speed-reducing transmission device connected between the power output shaft and the motor output shaft of the motor, wherein the motor is a flat motor and the speed-reducing transmission device is a worm-gear speed-reducing transmission device. The wire feeding device provided with the wire-feeding motor equipment further comprises a frame assembly and a support assembly. The welding system provided with the wire feeding device comprises welding power source equipment, a control device and a welding gun, wherein the control device comprises a voltage and/or current value detection module, a speed control module, voltage and/or current fluctuation detection equipment and a wire drawing and feeding control module. According to the invention, not only can the service life of the wire-feeding motor equipment and the service life of the wire feeding device be prolonged, but also the dynamic response speed of the wire-feeding motor equipment and the dynamic response speed of the wire feeding device are greatly improved, so that the dynamic response speed of the welding system, which meets the requirements of low spattering and even no spattering, is achieved during welding.