A liquid crystal display device includes a first substrate and a second substrate with a liquid crystal layer therebetween, a seal material joining the first substrate and the second substrate to each other, a plurality of gate signal lines and a plurality of drain signal lines, wherein the gate signal lines and the drain signal lines being formed on the first substrate, and a plurality of drive circuits connected to the first substrate. Data transmission signal lines are formed on the first substrate, wherein the data transmission signal lines are connected electrically between the drive circuits, and at least a part of at least one of the data transmission signal lines is positioned between the seal material and the first substrate.