Polyaniline is a conductive polymer that has electrochemical activity. For this reason, it has many different uses in electrochemical area. In this study, polyaniline was prepared by electrochemical oxidation of aniline in concentrated H2SO4 and HCl solutions. Then, membranes were obtained from a mixture of these polymers and paraffin at a weight ratio of 50%. Ion-selective electrodes were prepared with these membranes and AgCl/Ag electrodes. Properties of prepared membranes were investigated with potentiometric measurements made in HCl, KCl, H2SO4, and HClO4 Solutions of different concentrations. The E-logc plots obtained with these ion-selective electrodes were found to be linear in a distinct concentration range. Their slopes depend on the membrane type and the doping ion in the test solution. The difference between these membranes was explained according to the morphological structures of polyaniline membranes.