The utility model relates to a device for a water pressure test in a wire line coring borehole under the condition of no drilling, which has the advantages that under the condition of no drilling, a test section and water outside the test section are isolated to meet the water pressure test condition and ensure convenient and smooth water drain through a rubber pipe after test. In order to solve the problem, the utility model adopts the technical scheme that the device comprises a boring test section; a hollow drill rod is fixed to the top of the boring test section through a holder at an orifice; the upper end of the drill rod is coaxially connected with a hollow vertical shaft; a vertical shaft sleeve is matched with the vertical shaft and is connected with a vertical shaft chuck of a drilling machine; a drill bit is connected with the lower end of the drill rod; a reducer union suspended packer is arranged at the drill bit; and the interior of the packer is connected with a water pump positioned outside the borehole through the drill rod, the vertical shaft and a high-pressure rubber pipe in sequence. The utility model is mainly suitable for testing the permeability rate of rock masses in a wire line coring borehole with the aperture of 75 mm.