Embodiments of the present disclosure relate to a color filter structure and a preparation method therefor, and a display panel. The color filter structure (100) comprises: a plurality of color control units (102) located on a substrate (101), and a pixel defining layer (103) defining the plurality of color control units (102), wherein the plurality of color control units (102) are respectively defined in a plurality of openings 104 defined by the pixel defining layer (103); the pixel defining layer (103) comprises a plurality of spacer portions (105), each of the plurality of spacer portions (105) spaces two of the plurality of color control units (102) from each other, and an auxiliary portion (106) is provided on at least one side wall of the at least one spacer portion (105) facing the color control units (102); the compactness of the auxiliary portion (106) is greater than or equal to the compactness of the bottom of the spacer portion (105). Thus, flowing ink can be prevented from permeating into adjacent openings, thereby avoiding color crossover, thus avoiding the influence on a display effect.