A method of manufacturing a thin film transistor array panel includes: a gate insulating layer disposed on a gate electrode, a semiconductor disposed on the gate insulating layer, a source electrode opposite a drain electrode disposed on the semiconductor, a color filter disposed on the gate insulating layer, an overcoat disposed on the color filter and including an inorganic material. A first dry etching is performed using the photosensitive film pattern as a mask to etch the overcoat and provide a preliminary contact hole, through which a portion of the color filter is exposed. A second dry etching is performed using the overcoat as a mask to etch the color filter through the preliminary contact hole and to provide a contact hole, through which a portion of the drain electrode is exposed. A pixel electrode is connected to the drain electrode through the contact hole, on the overcoat.