Abstract: An apparatus and method for inspecting a liquid crystal display device is provided. The apparatus includes: a camera photographing a front surface of a liquid crystal panel; a back light irradiating light to the liquid crystal panel; a diffuser sheet diffusing the light generated from the back light; a prism sheet converting the diffused light so as to be perpendicularly incident to a rear surface of the liquid crystal panel; a probe unit applying an inspection signal to the liquid crystal panel; and a frequency converter converting a frequency of the light generated from the back light. The apparatus for inspecting the liquid crystal display device according to the invention detects bad sub-pixels, impossible to detect with the naked-eye, improving the quality of the liquid crystal display device.