A Cu/PMA–MIL-101(Cr) metal–organic-framework-coated microreactor has been applied in the 1,3-dipolar cycloaddition of benzyl azide and phenylactetylene (click chemistry). The Cu/PMA–MIL-101(Cr) catalyst was incorporated by using a washcoating method. The use of tetraethylorthosilicate (TEOS) and a copolymer pluronic F127 as binders resulted in a stable and uniform coating of 6 μm. The application of the Cu/PMA–MIL-101(Cr) capillary microreactor in the click-chemistry reaction resulted in a similar intrinsic activity as in the batch reactor, and a continuous production for more than 150 h time-on-stream could be achieved. The presence of water in the reagent feed led to reversible catalyst deactivation and was necessary to be removed to obtain a stable catalyst operation.