This research focuses on investigation of the characteristics of activated carbons derived from deoiled rice bran residues, a major by-product of the rice bran oil industry. The preparation of activated carbons consists of two steps; the first step is the pre-carbonized acid-leaching (H2SO4) process and the second step is chemical activation using H3PO4 or ZnCl2 as an activating agent for the development of the micropores. The effects of preparation parameters including the types of activating agent (H3PO4 and ZnCl2) and temperature of chemical activation were studied. The physical properties of samples were examined by means of XRD, SEM, TGA, and N-2-physisorption. The maximum BET surface areas obtained from ZnCl2 and H3PO4 activation are 1404m(2)/g and 1187m(2)/g, respectively. All activated carbons exhibited mostly microporous and partly mesoporous structures. These experimental results indicated that deoiled rice bran residues can be a promising economical source for the preparation of activated carbon.