A slide bearing, comprising: an upper case having a ring-shaped groove formed in a lower surface of an upper case body of the upper case; a lower case, which is rotatably combined with the upper case and has a ring-shaped lower case body having an insertion hole for inserting the strut assembly, and has a ring-shaped projection which is formed in an upper surface of the lower case facing the upper case and is inserted into the ring-shaped groove formed in the lower surface facing the lower case in order to form a ring-shaped space, the lower case having a ring-shaped mud guard which protrudes outward in a radial direction from an outer peripheral surface of the lower case; a ring-shaped center plate (4; 4a-d) which is placed between the upper case and the lower case; and a ring-shaped outer dust seal which is positioned on an outer peripheral side of the center plate; wherein the slide bearing further comprises a ring-shaped lubricating sheet (6; 6a) which is placed between the center plate and the upper case and/or between the center plate and the lower case; the ring-shaped outer dust seal has one end in the axial direction inclined outward in the radial direction and abutting, while being bent, directly against a groove bottom of the ring-shaped groove of the upper case or against a protective wall formed to protrude downward from the groove bottom of the ring-shaped groove of the upper case and another end in the axial direction abutting against an upper surface of the ring-shaped projection of the lower case; the center plate has a connecting part which extends outward in the radial direction from the outer peripheral side of the center plate and connects with the outer dust seal; and at least one of front and back surfaces (60, 61) of the lubricating sheet has a sliding surface which slides on a counter surface facing the lubricating sheet. an upper case having a ring-shaped groove formed in a lower surface of an upper case body of the upper case; a lower case, which is rotatably combined with the upper case and has a ring-shaped lower case body having an insertion hole for inserting the strut assembly, and has a ring-shaped projection which is formed in an upper surface of the lower case facing the upper case and is inserted into the ring-shaped groove formed in the lower surface facing the lower case in order to form a ring-shaped space, the lower case having a ring-shaped mud guard which protrudes outward in a radial direction from an outer peripheral surface of the lower case; a ring-shaped center plate (4; 4a-d) which is placed between the upper case and the lower case; and a ring-shaped outer dust seal which is positioned on an outer peripheral side of the center plate; wherein the slide bearing further comprises a ring-shaped lubricating sheet (6; 6a) which is placed between the center plate and the upper case and/or between the center plate and the lower case; the ring-shaped outer dust seal has one end in the axial direction inclined outward in the radial direction and abutting, while being bent, directly against a groove bottom of the ring-shaped groove of the upper case or against a protective wall formed to protrude downward from the groove bottom of the ring-shaped groove of the upper case and another end in the axial direction abutting against an upper surface of the ring-shaped projection of the lower case; the center plate has a connecting part which extends outward in the radial direction from the outer peripheral side of the center plate and connects with the outer dust seal; and at least one of front and back surfaces (60, 61) of the lubricating sheet has a sliding surface which slides on a counter surface facing the lubricating sheet.