All-polymer RC filter circuits by all-inkjet printing technology are fabricated for the first time. Conductive polymers such as polyaniline and poly(3, 4-ethylenedioxythiophene) have been used as the electrode material of the capacitor as well as the resistor material. The fabrication process and the characteristics of the printed capacitor and RC filter have been demonstrated. Simulation of the printed RC circuit has been demonstrated and compared with the experimental measurement results. A detail discussion has been given about the all-polymer capacitor and RC filter. (C) 2002 Elsevier Science Ltd. All rights reserved.