A facile method for the fabrication of negatively and positively charged rGO field effect transistors (FETs) is proposed, which utilizes electrostatic attraction between electrodes and rGO sheets. Negatively and positively charged rGO sheets are functionalized with carboxylic acid and amine groups, respectively. The FET of amine-functionalized rGO exhibits an n-doping effect. The FET devices fabricated by this method show high mobility of carriers.