The pH response of lower critical solution temperature (LCST) of N-isopropylacrylamide (NIPAAm)/N-[3-(dimethylamino)propyl] methacrylamide (DMAPM) copolymers was switched by combination with porous CaCO3 microbeads. Although LCST of the simple copolymer hydrogels increases with decreasing pH, the critical value of the copolymers trapped in the porous framework decreases with the pH drop. The inversion of the pH response is ascribed to change of the effect of DMAPM by the presence of an ionic inorganic surface.