The invention provides a plasma torch for dielectric heating, and relates to plasma equipment. The plasma torch is mainly composed of a front torch body, an anode, a rear torch body, a cathode and an insulation frame. The front torch body is provided with a guide sleeve and a cylinder extending backwards, and the guide sleeve is arranged in the inner space of the cylinder; the anode is embedded into the front torch body, the space between the cylinder of the front torch body and the wall of the anode forms a cooling water jacket, a cathode base is arranged on a rotary body structure of the rear torch body, the cathode is installed at the front end of the cathode base, and a cooling cavity is formed in the cathode. The front torch body is installed at the front end of the insulation frame, the extending cylinder of the front torch body is inserted into a front inserting port of the insulation frame, the rear torch body is installed at the rear end of the insulation frame, the cathode base on the rear torch body enters a rear inserting port of the insulation frame, the head of the cathode stretches into a cylindrical space in the rear portion of the anode, and the space between the head of the cathode and the wall of the rear portion of the anode forms an ionization channel. The plasma torch is used for pyrolyzing water to manufacture hydrogen or used for processing harmful substances, thereby reducing the dependence on coal and oil of people and preserving the ecological environment.