A novel pH-switchable macroscopic assembly is reported using alginate-based hydrogels functionalized with host (alpha-cyclodextrin, alpha CD) and guest (diethylenetriamine, DETA) moieties. Since the interaction of alpha CD and DETA is pH sensitive, the host hydrogel and guest hydrogel could adhere together when the pH is 11.5 and separate when the pH is 7.0. Furthermore, this pH-controlled adhesion and dissociation shows a good reversibility. The host and guest polymers have good biocompatibility; therefore, this pH-sensitive macroscopic assembly shows great potential in biotechnological and biomedical applications.