An in-plane switching mode liquid crystal display device, comprising first and second substrates attached to face each other; a liquid crystal layer between the first and second substrates; a first polarization film and a second polarization film on the first substrate and the second substrate, respectively, each of the first and second polarization films simultaneously performing an A-plate compensation film function and a polarization function, the first and second polarization films prevent light leakage in a horizontal direction; and a C-plate compensation film positioned on the second substrate, the C-plate compensation film prevents light leakage in a vertical direction.