The utility model discloses a part for a DLP (Digital Light Processing) photocuring 3D printing machine and particularly relates to a resin groove for the DLP photocuring 3D printing machine. The resin groove comprises a transparent groove body, wherein the bottom part of the transparent groove body is provided with through holes; a transparent soft layer is laid on the bottom part of the groove in a sealing manner; and the transparent soft layer can cover the through holes completely. The resin groove has the obvious advantages that the technical purpose of effective demolding of a printing layer and the bottom part of the resin groove in the DLP photocuring 3D printing machine is achieved, the energy is saved, the economic benefit is improved, and the surface finish of an object printed by the DLP photocuring 3D printing machine is also improved and the like.