An inspection apparatus for inspecting an end face of a transparent substrate and an inspection method for inspecting an end face of a transparent substrate according to the present invention are capable of reliably and accurately detecting defects at the end face of the transparent substrate. When a display panel substrate 10 which is a transparent substrate to placed on a rotating table 21, a light is intermittently emitted from an end-face illuminating unit 39 arranged opposite to the end face of the display panel substrate 10. The light emitted along the surface of the substrate 10 is reflected from a lower reflecting mirror 42 toward the end face of the transparent substrate 10. The end face and an adjacent portion thereof are imaged by a CCD camera 36. Defects at the end face of the display panel substrate 10 are detected based on an image density of each pixel in the obtained image data.