The invention relates to the technical field of lens detection and provides a lens testing device.The device comprises a base, a rear lens group sliding block, a front lens cone, a rear lens cone, a video board, an extinction ring, a front lens press ring, a rear lens press ring, a lens module, a turnplate and a pull rod, wherein the front lens cone is arranged in a first opening of a first supporting plate in a penetrating mode through the front lens press ring, the rear lens group sliding block is arranged on the upper surface of the base in a sliding mode, the rear lens cone is arranged at the end, close to the first opening, of a second opening in a penetrating mode, the rear lens press ring is arranged at the end, away from the first opening, of the rear lens cone, the other end of the rear lens press ring is connected with the extinction ring arranged in the second opening in a penetrating mode, the video board is fixedly arranged on a second supporting plate and located on the end face, away from the rear lens cone, of the extinction ring, and the lens module is arranged in a lens body formed by the front lens cone and the rear lens cone.The device solves the problems of existing lens testing devices that the devices are complicated, testing speed is low and production efficiency is low.