A color filter array substrate, a method for fabricating the same and a display device are disclosed. The color filter array substrate includes a plurality of gate lines and a plurality of data lines disposed as intersecting each other horizontally and vertically and a plurality of pixel regions defined by the gate lines and the data lines, each of the pixel regions includes a TFT, wherein each of the pixel regions further includes a band-pass filter layer, the band-pass filter layer transmits light within a specific wavelength range while reflects light of other wavelengths; the band-pass filter layer comprises a first medium sub-layer, a second medium sub-layer and a third medium sub-layer, the second medium layer is of different thicknesses at different pixel regions.