Langmuir isotherms of mixed monolayers of polyaniline and cadmium arachidate have been studied, and mixed monolayers have been transferred uniformly onto substrates as Langmuir-Blodgett (LB) multilayers. The LB films were characterized by XRD, W-Vis and FTIR spectroscopy, de conductivity and cyclic voltammetric measurements. The FTIR results suggest that the films contain arachidate salt, and the XRD results indicate the presence of a layered structure in the mixed LB films.