A slide bearing for supporting a load of an object of support, the slide bearing comprising: an upper case configured to receive the load of the object of support; a lower case rotatably combined with the upper case; and a center plate placed between the upper case and the lower case; the center plate having an upper surface, on which a bearing surface is formed, and lower surface, both of which are in a shape of a substantial conical surface, the bearing surface including a grease groove to function as a grease reservoir; the upper case having a load transmission surface in a shape of substantial conical surface; and the lower case having a supporting surface in a shape of a substantial conical surface, the supporting surface being in contact with the lower surface of the center plate; characterized in that the slide bearing further comprises a lubricating sheet placed between the center plate and the upper case, and having an upper surface and a lower surface, both of which are in a shape of a substantial conical surface, a slide surface formed on the lower surface of the lubricating sheet being in contact with the bearing surface of the center plate, the load transmission surface being in contact with the upper surface of the lubricating sheet; the lower case further having detents annularly formed on an outer circumferential side of the supporting surface, the detents having flat sections and protruding sections protruding from the flat sections towards the upper case, the flat sections and the protruding sections being alternately placed; the center plate further having convex detents projecting radially outwardly from an outer peripheral surface of the center plate; and the convex detents of the center plate being configured to engage with the protruding sections of the detents of the lower case to prevent the center plate from rotating relative to the lower case. an upper case configured to receive the load of the object of support; a lower case rotatably combined with the upper case; and a center plate placed between the upper case and the lower case; the center plate having an upper surface, on which a bearing surface is formed, and lower surface, both of which are in a shape of a substantial conical surface, the bearing surface including a grease groove to function as a grease reservoir; the upper case having a load transmission surface in a shape of substantial conical surface; and the lower case having a supporting surface in a shape of a substantial conical surface, the supporting surface being in contact with the lower surface of the center plate; characterized in that the slide bearing further comprises a lubricating sheet placed between the center plate and the upper case, and having an upper surface and a lower surface, both of which are in a shape of a substantial conical surface, a slide surface formed on the lower surface of the lubricating sheet being in contact with the bearing surface of the center plate, the load transmission surface being in contact with the upper surface of the lubricating sheet; the lower case further having detents annularly formed on an outer circumferential side of the supporting surface, the detents having flat sections and protruding sections protruding from the flat sections towards the upper case, the flat sections and the protruding sections being alternately placed; the center plate further having convex detents projecting radially outwardly from an outer peripheral surface of the center plate; and the convex detents of the center plate being configured to engage with the protruding sections of the detents of the lower case to prevent the center plate from rotating relative to the lower case.