Provided are TFT-LCD panel, method for preparing the same, and TFT display device. The TFT-LCD panel includes an upper polarizer, a positive birefringence polymer substrate, a liquid crystal layer, a negative birefringence polymer substrate and a lower polarizer, wherein the positive birefringence polymer substrate and the negative birefringence polymer substrate locate at an upper side and an lower side of the liquid crystal layer respectively, the upper polarizer locates at an upper surface of the positive birefringence polymer substrate, the lower polarizer locates at a lower surface of the negative birefringence polymer substrate; the positive birefringence polymer substrate and the negative birefringence polymer substrate are equals in a birefringence retardation in an original birefringence state, and are equals in a birefringence retardation of in the photo-elasticity birefringence state. The TFT-LCD panel of the present disclosure may avoid generating light leakage in dark, and improve homogeneity in dark.