A device for testing cameras which is adaptable for testing optical devices of different sizes and types includes a holder, a top plate, and an illumination assembly. The holder includes a frame. The top plate is disposed on the frame. The illumination assembly includes a lamp holder and an illumination module. The lamp holder is slidably disposed on a surface of the top plate facing away from the frame in a first direction. The illumination module, wherein the illumination module is slidably disposed on the lamp holder facing away from the frame in a second direction.