A cleaner comprising: a body; a first rotating plate and a second rotating plate rotatably coupled to the body; a first mop configured to be detachably attached to a bottom surface of the first rotating plate; a second mop configured to be detachably attached to a bottom surface of the second rotating plate; a first support wheel coupled to the body; a second support wheel coupled to the body at the same side of the first support wheel with respect to a horizontal connection line connecting a center of the first rotating plate to a center of the second rotating plate; and an auxiliary wheel coupled to the body at the other side of the first support wheel with respect to the connection line, wherein a lowest part of the first rotating plate is positioned above a first reference line connecting a lowest part of the first support wheel to a lowest part of the auxiliary wheel, and a lowest part of the first mop is positioned below the first reference line, a lowest part of the second rotating plate is positioned above a second reference line connecting a lowest part of the second support wheel to the lowest part of the auxiliary wheel, and a lowest part of the second mop is positioned below the second reference line, and wherein the first rotating plate and the second rotating plate are inclined with respect to the connection line such that interior sides of the first rotating plate and the second rotating plate that are closer to each other are spaced further from the floor surface than exterior sides of the first rotating plate and the second rotating plate that are relatively farther from each other, wherein, when the first and second rotating plates (10, 20) rotates, frictional force is generated between the bottom surface of the first and second mop (30, 40) and the floor surface to move the cleaner along the floor surface. a body; a first rotating plate and a second rotating plate rotatably coupled to the body; a first mop configured to be detachably attached to a bottom surface of the first rotating plate; a second mop configured to be detachably attached to a bottom surface of the second rotating plate; a first support wheel coupled to the body; a second support wheel coupled to the body at the same side of the first support wheel with respect to a horizontal connection line connecting a center of the first rotating plate to a center of the second rotating plate; and an auxiliary wheel coupled to the body at the other side of the first support wheel with respect to the connection line, wherein a lowest part of the first rotating plate is positioned above a first reference line connecting a lowest part of the first support wheel to a lowest part of the auxiliary wheel, and a lowest part of the first mop is positioned below the first reference line, a lowest part of the second rotating plate is positioned above a second reference line connecting a lowest part of the second support wheel to the lowest part of the auxiliary wheel, and a lowest part of the second mop is positioned below the second reference line, and wherein the first rotating plate and the second rotating plate are inclined with respect to the connection line such that interior sides of the first rotating plate and the second rotating plate that are closer to each other are spaced further from the floor surface than exterior sides of the first rotating plate and the second rotating plate that are relatively farther from each other, wherein, when the first and second rotating plates (10, 20) rotates, frictional force is generated between the bottom surface of the first and second mop (30, 40) and the floor surface to move the cleaner along the floor surface.