This book provides useful information about conductive polymers such as polyaniline and its synthesis methods, characterizations and doping with new generation of organic molecular as ionic liquids. They would be widely applied in the research of chemical modified electrodes, storage batteries, light-emitting diodes, fixation enzymes and so on. Additionally, this book elucidates and illustrates further innovative various techniques have been used to synthesize PANI, electrochemical synthesis, chemical synthesis and so on. We have also studying the influence of some ionic liquids in the synthesis of the polyaniline by chemical and electrochemical methods, with an aim of widening the electroactivity range with a better stability of this polymer. This book also discusses our researches works for the study to doping of polyaniline by ionic liquids with different anions and its applications for the fabrications of chelcognied junctions, mechanical study of composite with other polymers.