The invention discloses a slide-cover type gate plate for petroleum pipeline transportation. The slide-cover type gate plate comprises a disc body, a trapezoidal clamping groove is formed at the upper edge of the disc body, bearing surfaces are arranged on the outer surfaces of the disc body, and a rectangular buffering recessed area is arranged at the center of the bearing surface on one side; a boss with a rectangular cross section is arranged at the center of the rectangular buffering recessed area, sliding rails are mounted on two sides of the rectangular buffering recessed area, and a slide cover is inserted into the sliding rails and covers the surface of the rectangular buffering recessed area. The slide-cover type gate plate has the advantages that good blocking and buffering effects are achieved, when liquid petroleum impacts a buffering recess, vortex turbulence is formed, and accordingly impact of the petroleum on the gate plate is reduced; the profile is matched with the cross section of a petroleum pipeline, the disc body can be fastened with the wall of the petroleum pipeline in a matched manner, sealing performance and water resistance of the slide-cover type gate plate are further improved, and the slide-cover type gate plate is beneficial to popularization and application in the petroleum transportation industry.