Electrochemical regeneration of NADH was performed in a new type of reactors: membrane electrochemical reactor (MER). The principle of these reactors is to confine the catalyst near the electrode thanks to a dialysis membrane (D-MER) and an ultrafiltration membrane (UF-MER). Several experimental conditions have been tested in the case of the synthesis of cyclohexanol from cyclohexanone. The best results (100% in 70 h) obtained in recycling mode with a rhodium complex as electrochemical mediator showed the potentiality of UF-MER as a process coupling a catalytic system and an electrochemical reaction.