Phosphorescent materials have received considerable attention in organic solar cells (OSCs) due to their long emission lifetime and inhibited geminate recombination. Motivated by its particular photophysical property, herein, the spatially addressable bis(2‐benzo[b]thiophen‐2‐ylpyridine)(acetylacetonate)iridium(III) (Ir(bt)2(acac))/polystyrene‐b‐poly(4‐vinylpyridine) (PS‐b‐P4VP) as a photoactive floating‐gate is first demonstrated to explore the application of phosphorescent material on the photo‐responsive characteristics of photomemory and artificial photonic synapse. By manipulating the interfacial area between Ir(bt)2(acac)/PS‐b‐P4VP and active channel by a solvent annealing process, an ON/OFF current ratio of 103 and a low programming time of 700 ms can be achieved. The current study addresses the exciton lifetime of photoactive material functions in photomemory and highlights the interfacial area between photoactive materials and charge‐carrier transporting materials in reducing photo‐programming time.