A liquid crystal display device includes a thin film transistor (TFT) array substrate, an anisotropic conductive adhesive film, a chip, a flexible printed circuit, a color filter substrate, a polarizer, and a protective layer. The TFT array substrate includes an output terminal region, an input terminal region, first test signal wires, and second test signal wires. The second test signal wires are connected to the first test signal wires in an out-of-array wiring region. Material of the first test signal wires is titanium aluminum alloy, and material of the second test signal wires is polycrystalline silicon.