An organic light-emitting diode (OLED) display is disclosed. In one aspect, the OLED display includes a substrate including a pixel region including a plurality of pixels. A plurality of lighting test transistors is formed in a peripheral region surrounding the pixel region and electrically connected to the pixels, and the lighting test transistors are configured to test lighting of the pixels. Each of the lighting test transistors includes a first active layer pattern formed over the substrate, a first gate electrode formed over the first active layer pattern, and a conductive pattern formed over the first gate electrodes. The conductive pattern is electrically connected to the first gate electrode, the first gate electrodes are spaced apart from each other and have substantially the same shape, and the conductive patterns are integrally formed.