Electrochemical polymerization of aniline was performed by the method of ultramicroelectrode cyclic voltammetry in the lamellar liquid crystal and hexagonal liquid crystal of SDS/n-C5H11OH/H2SO4(aq) system. The results indicate that the electrochemical polymerization of aniline can be catalyzed by the SDS/n-C5H11OH/ H2SO4(aq) lyotropic liquid crystal. The polymerization potential of aniline is smaller in the lyotropic liquid crystal system than that in the 0.10 mol L-1 sulfuric acid solution. The catalytic efficiency and polymerization rate of aniline increase with the n-pentanol content, but decrease with the increase of the SDS content or [PhNH2/ H2SO4(aq)] content. Moreover, the catalytic efficiency of the lamellar liquid crystal exceeds that of the hexagonal liquid crystal in the SDS/n-C5H11OH/H2SO4(aq) system. (c) 2006 Wiley Periodicals, Inc.