A device for the formation of a prosthetic plane of the upper jaw check-bite in the course of the prosthodontic treatment of the patients with completely absent dentition was developed in order to improve the formation of the prosthetic plane during complete removable laminar dentures manufacturing. The objective was achieved by the fact that the bite plate of the device was made in the form of U-shaped supporting ruler with a fork-like extension on both sides and with a pocket in the central part. The bite plates for the frontal and chewing parts of the upper jaw check-bite were inserted into the pocket. The bite plates were made removable, the frontal plate was T-shaped, and the chewing one was fork-like with rounded forks. The device was additionally equipped with a movable ruler to record strict parallel alignment in relation to the Camper and inter-pupillary lines. The supporting ruler was equipped with two vertical columns of square shape with symmetric millimeter scales, along which the vertical movements of the movable ruler were conducted and its parallel alignment was recorded in relation to the supporting ruler. The movable ruler was additionally equipped with a leveling device fixed in its central part to position the patient’s head relative to the horizon line. The use of bite plates for the frontal and chewing parts of the upper jaw check-bite and the provision of structural elements in the form of the supporting and movable rulers with the possibility of moving the movable ruler on the vertical columns of the supporting ruler provide a fast, comfortable, precise and uniform formation of the prosthetic plane of the upper jaw check-bite parallel to the Camper and inter-pupillary lines in the prosthodontic treatment of the patients with completely absent dentition.