The invention provides a color film substrate, a preparation method for the color film substrate, a display panel and a display device. The color film substrate includes a base, and the base includes pixel regions and spacer regions between the pixel regions; each pixel region is provided with a color film layer, and each spacer region is provided with a black matrix and an insulation layer; the insulation layer is positioned on the side, back to the base, of the black matrix, and the positive projection of the insulation layer on the base completely covers the black matrix so as to prevent capacitance from being formed between the black matrix and an array substrate. According to the color film substrate, by arranging the insulation layer, insulation spacing arrangement is formed between the black matrix and the array substrate so as to prevent the capacitance from being formed between the black matrix with a low resistance and the conductive film of a corresponding region on the array substrate, which prevents charges from being accumulated between the black matrix and the conductive film of the corresponding region on the array substrate; therefore, it is avoided that when displaying, a display product which uses the color film substrate produces residual images or the unevenness of black and white cloud displaying and other electric undesirable phenomena, which improves the display effect of the display product.