A stereoscopic image display device includes a first substrate defining an active area and a non-active area surrounding the active area, the first substrate having a gate line formed at the active area and the non-active area, a gate pad formed at the non-active area, a dummy line defining a dummy pixel by crossing the gate line, and a light leakage blocking layer that is connected to the dummy line and disposed to overlap the gate line and the gate pad; a second substrate opposing the first substrate, the second substrate having a black stripe on a side of the second substrate opposite from the first substrate along portions corresponding to edges of the active area, and a patterned retardation film over the black stripe; and a liquid crystal layer disposed between the first and second substrates.