Electropolymerization of pyrrole in the aqueous electrolyte solutions of potassium chloride was investigated by means of chronoamperometric, in situ electrochemical quartz crystal oscillator and optical microscopic methods. polypyrrole patterns of one dot, two dots and three dots of triangle were successfully formed at gold electrode surfaces in aqueous solutions of pyrrole and were confirmed ex situ by optical microscopy. Further development of the technique and possible applications are discussed.