The invention discloses a casing pipe type gas electric heating device. The device comprises a gas inlet, a gas outlet, a shell, an inner pipe, an outer pipe, an electric heating wire, fins, a heat insulation layer and other components; the casing pipe type structural design is adopted in the gas electric heating device, the spiral fins are arranged outside the inner pipe, the electric heating wire is wound on the outer surface of the inner pipe along a gap between two adjacent spiral fins, the outer pipe is arranged on the outer sides of the fins, a whole casing pipe is fixed in the shell, and the heat insulation layer is arranged between the outer pipe and the shell. A spiral winding gas flow way is formed between the spiral fins and the outer pipe, the gas flow way is prolonged, and the device is high in heating speed and uniform in gas heating; heated gas flows through the winding type flow way on the outer side of the inner pipe, is heated to a certain temperature and then is reheated through the inner side of the inner pipe, the wall temperature of the outer pipe is relatively low, meanwhile, the heat insulation layer is arranged between the shell and the outer pipe of the electric heating device, heat dissipation losses are reduced, and the heat efficiency of the device is improved.