The present application provides a color film substrate, a display device, and a color film substrate fabricating method. The color film substrate comprises a display region and a non-display region, wherein the color film substrate in the non-display region comprises: a base; and a photoresist layer disposed on the base; a planarization layer disposed on a side of the photoresist layer away from the base; a support layer disposed on a side of the planarization layer away from the base; wherein a total thickness of the photoresist layer, the planarization layer, and the support layer is greater than or equal to a first thickness threshold.