The invention discloses a rotary valve type pump protecting device. The problems that an existing pump protecting device is complex to operate and high in equipment investment, and safety needs to be further improved are solved. According to the technical scheme, the rotary valve type pump protecting device comprises a sealing valve body with a first flow channel, and a check valve is arranged in the first flow channel; the device further comprises a bypass valve body with a second flow channel, and the part, blow the check valve, of the first flow channel communicates with the second flow channel through a flow hole in a ball valve; the ball valve is fixedly connected with one end of a guide rod, and the other end of the guide rod is hinged to the check valve. The rotary valve type pump protecting device is simple in structure, free of manual operation, controllable in pressure, low in cost, efficient and safe.