A thin film transistor substrate including a pixel region constructed with pixels, includes: gate signal lines provided in the pixel region and extending in a first direction; gate lead-out lines provided in the pixel region and extending in a second direction; a thin film transistor and a pixel electrode provided in each of the pixels; a common electrode provided across the pixels; and a common line electrically connected to the common electrode. The gate signal lines and the gate lead-out lines are connected to each other through a first contact hole at at least one of a plurality of intersections of the gate signal lines and the gate lead-out lines, and the common line covers the first contact hole in planar view of the thin film transistor substrate.