Abstract An original, substrate‐selective nanoreactor is designed and characterized. The nanoreactor made of a 4‐nitrophonel (NP)‐imprinted polymer and Ag nanoparticles, can specifically recognize NP compared with its analogues 4‐nitrophenyl acetate (NPA) and 2,6‐dimethyl‐4‐nitrophenol (DNP). Under comparable conditions, this nanoreactor significantly accelerated the reduction of NP; however, much less acceleration is shown for its analogues. Unlike traditional Ag nanoreactors, which lack molecular recognition abilities, this unique nanoreactor is composed of molecularly imprinted networks, making substrate‐selective catalysis feasible.