Artificial anal prosthesis. It comprises a hemispherical medical soft cap embedded with a sensor, wherein exhaust holes are distributed on the spherical surface of the soft cap, the big end of the soft cap is provided with an exhaust nut connected with the sensor shell, and the sensor probe slides through the sensor from its central hole; A hollow soft sealing plug with fleshy silica gel is provided with a protrusion for sealing the intestinal tract, and the end face is provided with a vent hole, and a sensor and a piston connecting rod connected with the sensor are arranged in the plug; Incremental silica gel soft button with piston connecting rod mechanism. The exhaust passage provided by the utility model has smooth exhaust. The prosthesis is soft, with little foreign body sensation, quick disassembly and easy cleaning. After radical resection of rectal cancer, the patient can still keep the anus in situ and normal defecation process after removing the complete focus anal tissue, which solves many inconveniences and pains caused by the left lower abdominal wall ostomy in the prior art, and provides convenience for the patient without the help of others. It provides convenience for patients who have no help.