A method of inspecting a display panel, which is capable of substantially minimizing a color difference of a display panel according to a viewing angle, includes: setting a reference area having a center point on a chromaticity diagram; emitting a white light on the display panel; measuring first color coordinates of a target point of the display panel at a first viewing angle; measuring second color coordinates of the target point at a second viewing angle; calculating a difference value between the first color coordinates and the second color coordinates; converting the difference value into target polar coordinates with the center point as an origin; and determining whether the target polar coordinates are within the reference area.