AbstractA novel catalyst has been afforded by immobilizing Cu(OAc)2 salt to polydopamine‐coated magnetite (Fe3O4). The catalytic platform (Fe3O4@PDA@Cu) was fully characterized by Fourier transform infrared, Energy‐dispersive X‐ray, Scanning Electron Microscopy, and Thermogravimetric Analysis. The catalytic activity of the Fe3O4@PDA@Cu nanocatalyst was investigated in a green and effective synthesis of click reaction by applying three‐component reactions of azide, alkyne, and benzyl surrogates in water, providing the corresponding 1,2,3‐triazoles in high yield. Furthermore, the present nanocatalyst could be easily separated by an external magnet and reused several times without considerable reduction of its catalytic efficiency. Operational simplicity, environmental friendliness, economical processing, and easy workup are the features of the present protocol.