Benefiting from the structures of membrane and microchannel, catalytic membrane microreactors are attractive for multiphase catalytic reactions. In addition to the membrane development, the fabrication of an efficient catalyst layer on a supporting layer is also significant for improving the performance of the membrane microreactor. In the present study, a plate-type catalytic membrane microreactor with the catalyst layer prepared by the layer-by-layer self-assembly technology along with the in situ adsorption and reduction was proposed. Herein, polydopamine (PDA) and polyelectrolyte multilayers (PEMs) were coated on the surface of the polydimethylsiloxane supporting membrane to adsorb more PdCl42- ions for the subsequent reduction. The synthesized catalyst layer termed as PDA/PEMs/Pd was characterized by analyzing the chemical composition and surface morphology. In addition, the catalytic performance of the developed microreactor was tested by using hydrogenation of nitrobenzene. The results showed that the use of both PDA and PEMs for preparing the catlayst layer yielded better conversion and durability than the use of PDA or PEMs alone. Besides, the nitrobenzene solution flow rate had an adverse impact of the nitrobenzene conversion resulting from the decreased residence time. With the increase of the hydrogen flow rate, the nitrobenzene conversion could be improved due to the increased gas permeation. The nirobenzene conversion also increased with a reduction in the initial concentration of nitrobenzene. In short, employing the layer-by-layer self-assembly technology for the catalyst layer preparation is promising for catalytic membrane microreactors toward multiphase catalytic reactions.