The invention discloses a pH-sensitive composite hollow microsphere and a preparation method thereof, and relates to an intelligent material and a preparation method thereof. The preparation method comprises the following steps of: firstly, based on a polymerizable maleic acid iso-alcohol diester as a surfactant, adding styrene and vinyl pyridine to react so as to obtain poly(maleic acid iso-alcohol diester-styrene-vinyl pyridine) nano spheres with nuclear shell structures; and secondly, based on the mutual action and the compatibility difference to different solutions of the poly(maleic acid iso-alcohol diester-styrene-vinyl pyridine) nano spheres, carrying out secondary assembly at a two-phase interface so as to form the composite hollow microsphere with pH sensitivity. The composite hollow microsphere is assembled by a plurality of microspheres, the composite hollow microsphere can be disassembled when changing the pH, and the pH response value can be controlled by adjusting the ratio of styrene to vinyl pyridine, so that the method is simple, and the microsphere is a novel intelligent material with great potential.