An aggregation-induced emission (AIE) based smart singlet oxygen (¹O₂) generation system has been successfully fabricated based on supramolecular host–guest assembly. The controllable ¹O₂ generation can be achieved by conveniently changing the molar ratio between the macrocyclic host (WP5) and the guest molecule (TPEPY). Moreover, reversible control of ¹O₂ generation and fluorescence emission of supramolecular nanoassemblies can be achieved VIA adding Fe³⁺ and EDTA, which allows qualitatively monitoring the singlet oxygen generation efficiency by the naked eye.