The invention relates to the technical field of pulp screening equipment and discloses an up-flow type pressure screen which comprises a casing. Multi-layer partition plates are arranged in the casing and divide the inside of the casing into multiple discharging layers, the discharging layers are provided with discharging ports, the bottom of the casing is provided with a speed reduction motor, the speed reduction motor is provided with a rotating shaft penetrating the top of the casing, the rotating shaft is sleeved with a screen cylinder penetrating the multi-layer partition plates, the screen cylinder is internally hollow and is conical, the upper end of the screen cylinder is a small end, the lower end of the screen cylinder is a large end, a plurality of screen holes are evenly distributed in the surface of the screen cylinder, and the diameters of the screen holes are sequentially reduced in the direction from the lower end to the upper end of the screen cylinder. The top of the casing is provided with an air suction channel, a fan wheel is disposed in the air suction channel, the upper end of the rotating shaft is fixedly connected with the lower end of the fan wheel, the upper end of the air suction channel is rotatably connected with a cover plate, and the upper end of the casing is further provided with a feeding port. Through the up-flow type pressure screen, fibrous residue in pulp can be effectively separated, and the service life of a device can be prolonged.