Drainage device for at least partial installation in the floor of a room, comprising - a drainage body, which can be installed at a predeterminable height above the unfinished floor of a room, wherein the drainage body has an inlet opening and an outlet opening (3, 4), - a plurality of supports, which can hold the drainage body, wherein each of the supports comprises a rod, which extends upwards from the unfinished floor when the drainage device is installed, - clamping means, which allow the drainage body to be fixed to the supports at different heights, wherein the clamping means comprise two mutually interacting contours (17, 19), which can be rotated relative to one another, wherein, in a first relative position of the two mutually interacting contours (17, 19) it is possible to alter the height of the drainage body relative to the supports, whereas, in a second relative position of the two mutually interacting contours (17, 19), which differs from the first, the height of the drainage body relative to the supports is fixed, wherein the contour on the outside of the rod has three of four projections (18, 30, 31) protruding radially outwards or peripherally adjacent sections (28, 29), which protrude alternately more or less far radially outwards, wherein the projections (18, 30, 31) or the sections (28, 29) are part of the clamping means, - a plurality of recesses, which are connected to the drainage body or arranged on the drainage body, wherein, each one of the rods can engage in one of the recesses, wherein, each one of the contours (17, 19) is arranged or formed on the insides of the recesses, which are part of the clamping means, and wherein the contour has projections protruding radial inwards or peripherally adjacent sections (20, 21) on the inside of the recess, which protrude alternately more or less far radially inwards, wherein the drainage device comprises a plurality of plugs, which can each be applied to the top of the rods and which have a cover plate, as well as three or four bars protruding downwards from the cover plate, wherein the bars extend precisely into the spaces between the projections (18, 30, 31) of the contour of the particular rod, wherein the rod connected to the plug can be rotated in the circumferential direction by rotating the plug. - a drainage body, which can be installed at a predeterminable height above the unfinished floor of a room, wherein the drainage body has an inlet opening and an outlet opening (3, 4), - a plurality of supports, which can hold the drainage body, wherein each of the supports comprises a rod, which extends upwards from the unfinished floor when the drainage device is installed, - clamping means, which allow the drainage body to be fixed to the supports at different heights, wherein the clamping means comprise two mutually interacting contours (17, 19), which can be rotated relative to one another, wherein, in a first relative position of the two mutually interacting contours (17, 19) it is possible to alter the height of the drainage body relative to the supports, whereas, in a second relative position of the two mutually interacting contours (17, 19), which differs from the first, the height of the drainage body relative to the supports is fixed, wherein the contour on the outside of the rod has three of four projections (18, 30, 31) protruding radially outwards or peripherally adjacent sections (28, 29), which protrude alternately more or less far radially outwards, wherein the projections (18, 30, 31) or the sections (28, 29) are part of the clamping means, - a plurality of recesses, which are connected to the drainage body or arranged on the drainage body, wherein, each one of the rods can engage in one of the recesses, wherein, each one of the contours (17, 19) is arranged or formed on the insides of the recesses, which are part of the clamping means, and wherein the contour has projections protruding radial inwards or peripherally adjacent sections (20, 21) on the inside of the recess, which protrude alternately more or less far radially inwards,