The embodiment is to provide a liquid crystal display device capable of detecting malfunctions. The liquid crystal display device includes pixels configured to be connected to scan lines and data lines, data pads electrically connected to the data lines, a data integrated circuit supplying data signals to the data lines through the data pads, first data transistors coupled to the data pads, and second data transistors coupled to the data lines. The first data transistors are disposed on the data integrated circuit and the second data transistors are separated from the data integrated circuit.