PURPOSE: An apparatus for inspecting automatically a defect of an inner curve surface of a Braun tube is provided to detect correctly the defect of the inner curve surface by maintaining equally an incident ray of a light source and a photographing angle of a camera to an inspecting position of the inner curve surface. CONSTITUTION: An apparatus for inspecting automatically a defect of an inner curve of a Braun tube includes a transferring portion(10), a light source(4), a camera(5), and an inspection position compensation portion(20). The transferring portion transfers horizontally a Braun tube. The light source irradiates the light to an inspection position of the inner curve of the Braun tube. The camera is used for photographing the inspection position. The inspection position compensation portion includes a curvature member(22), a movable installation plate(21) having a roller(21a), and a rotation and vertical guide portion(23). The curvature member is moved by the driving force of a motor(24). The movable installation plate is rotated or moved along a curved side when the curvature member is moved.