Environmental friendly method used for synthesizing polyaniline was developed in this research. Nitrogen pulsed plasma generated from a theta-pinch device was selected for the polymerization. This is because it is easier to control plasma exposure using pulsed plasma than conventional continuous plasma. Moreover, this dry method can polymerize monomers into a polymer with few seconds. 0.1 M of aniline in 1.0 M of sulfuric acid aqueous solution was coated on a glass substrate and placed in a theta-pinch device. This device was then operated at a pressure of 20 kV, a voltage of 20 kV and a discharging current of 125 kA using nitrogen gas in order to generate nitrogen pulsed plasma. FTIR spectra of the obtained polyanilines synthesized using various numbers of the plasma shots exhibited the characteristic peaks of polyaniline at 1627 and 1403 cm-1. In addition, these polymers also showed UV-VIS absorption bands at 260 nm and 283 nm except for those synthesized using 15 and 20 shots of plasma. They exhibited the absorption band at 288 and 285 nm, respectively due to the formation of the sulfonic acid group on polyaniline molecule as confirmed by FTIR spectra at 1283 cm-1. While plasma exposure at 5 and 10 shots of plasma was not enough for the functionalization, at 25 and 30 shots of plasma, plasma exposure was too high and instead caused the scission of the functional groups.