The utility model discloses a worktable for a DLP photocuring 3D printer and particularly relates to a demoulding sunken type worktable for a DLP photocuring 3D printer. An installation bottom frame for fixing a transparent resin groove is arranged above a base face of the worktable, and the installation bottom frame is connected with the base face of the worktable by virtue of an elastic assembly and the installation bottom frame and the worktable are parallel; a first flange is further arranged at the edge on one side of the installation bottom frame, a servo motor which controls an output shaft to angularly displace when a demoulding signal of a printing layer and a bottom face of the transparent resin groove is received is arranged below the base face of the worktable, and the output shaft of the servo motor is connected with the first flange by virtue of a cam connecting rod structure. The worktable solves the technical problem that the installation bottom frame can be obliquely deviated relative to the base plate of the worktable when the printing layer and the groove bottom face of the transparent resin groove are demoulded and the DLP photocuring 3D printer works, so that the product printing quality of the DLP photocuring 3D printer can be enhanced.