A hydrology drill hole layered water pumping test same-diameter water seal device comprises a water pumping sleeve connecting segment 1and an upper core tube 2, a slide plate gland3, a pull rod nut 4, a slide plate 5, a pull rod 6, an upper core tube joint 7, a lower core tube joint 8, a positioning nut9, a positioning slips 10, a slips guide rail 11, a cone body 12, a lower core tube 13, an upper compression plate 14, a water seal rubber sleeve15, and a lower compression plate 16; in water pumping test, the water pumping sleeve goes down to the water seal position, and is pulled upwards; meanwhile, the positioning slips 10 is clamped on a hole wall under gravity; the lower compression plate 16 compresses the water seal rubber sleeve 15 upwards, thus segmenting a drill hole; when the water pumping test is done, the water pumping sleeve is rotated clockwise; the left-hand thread between the upper core tube joint 7 and the lower core tube joint 8 is opened, and the water pumping sleeve is pulled upwards; the slide plate 5 drives the pull rod 6 so as to enable the positioning slips 10 to leave the hole wall, thus pulling the water seal device from the drill hole.