Disclosed are a filter unit, a color film structure, a display panel, and a display device. The filter unit includes a color resist aperture. The color resist aperture is configured to accommodate a color resist. At least part of edges of an opening of the color resist aperture have equal distances to a geometric center of the opening. The structure of the color resist aperture of the filter unit is improved, such that at least part of edges of an opening of the color resist aperture have equal distances to the geometric center of the opening.