The utility model relates to an anti-reverse rotation device of a vertical long axle pump, which comprises a pump shaft and a bearing seat and is characterized in that the bearing seat is provided with an anti-reverse rotation disk; an anti-reverse rotation end cap is fixed onto the pump shaft and is correspondingly parallel to the anti-reverse rotation disk which is provided with a plurality of slope slots which are distributed along the circumference on the anti-reverse rotation disk; one end of each slope slot is a slope which is tangential with the end surface of the anti-reverse-rotation disk, and the other end of the slope slot is vertical to the end surface of the anti-reverse rotation disk; the anti-reverse rotation end cap is provided with a plurality of pin holes corresponding to the number of the slope slots on the anti-reverse rotation disk; anti-reverse rotation pins are arranged in the pin holes, and the directions of all the slope slots are the same; the anti-reverse rotation pin is in a columnar shape, and the anti-reverse rotation end cap is provided with the pin holes of which the number is relative prime to that of the slope slots on the anti-reverse rotation disk. The utility model has the advantages that the device can realize the anti-reverse rotation performance of the vertical long axle pump by simple structure.