The invention relates to a novel horizontal tube type sedimentation pond. The novel horizontal tube type sedimentation pond comprises an upper precipitation separation device and a lower precipitation sludge discharging device, wherein the precipitation separation device comprises horizontal tube units and sludge chutes; each horizontal tube unit comprises an inclined plate, and a plurality of separating plates which are arranged at intervals on the lower side surface of each inclined plate; each separating plate is a V-shaped plate consisting of a surface A and a surface B, and an opening of the section of each V-shaped plate is toward the corresponding inclined plate; each surface A is arranged on the side surface of the corresponding inclined plate; all surfaces A are parallel to each other; the planes of the surfaces B are parallel to or intersected with the plane of the corresponding inclined plates; all surfaces B are parallel to each other; a sludge discharging opening is left between every two adjacent separating plates on the same inclined plate. The novel horizontal tube type sedimentation pond has the advantages that the horizontal tube units comprise the inclined plates and the separating plates, so that the convenience of processing, manufacturing and mounting is ensured; channels being narrow in upper part and wide in lower part can be formed by the sludge chutes between adjacent horizontal tube units, so that the distribution condition that more sludge is at the lower part of each sludge chute and less sludge is at the upper part of each sludge chute apply is adapted, and as a result, the high efficiency of the precipitation separation device can be ensured.