The embodiment of the invention provides a downhole electric heating producing well pipe string structure and an oil production method thereof. The pipe string structure comprises a casing pipe, a horizontal screen pipe and a blind pipe. An oil pipe is arranged in the casing pipe. The rear end of the oil pipe is connected with a liner pipe. The liner pipe is located in the horizontal screen pipe and the blind pipe. The pipe string structure further comprises a scour pipe downwards extending into the oil pipe, the liner pipe and the blind pipe in sequence from a wellhead. A heating cable is wound on the inner wall of the liner pipe. A first annulus among the horizontal screen pipe, the blind pipe and the liner pipe is filled with solid catalyst particles with the particle size being greater than a gap of the horizontal screen pipe. A firs check valve and a second check valve are mounted at the front end and the rear end of the first annulus correspondingly. An outlet of the first check valve is pointed to the outside of the first annulus. An outlet of the second check valve is pointed to the inside of the first annulus. A filtering ring is arranged outside the second check valve and filled with filtering materials. The inner diameter of pores of the filtering materials is smaller than the particle size of the solid catalyst particles. Through the downhole electric heating producing well pipe string structure and the oil production method thereof provided by the embodiment of the invention, the modification effect of crude oil can be improved.