Starch-derived mesoporous carbons (SMCs) with well-developed mesoporosity were prepared by simultaneous template method, wherein the template and the carbon precursor were simultaneously synthesized. The synthesis mechanism and the effect of crystallization time on the pore structure of the resultant SMCs were investigated by N-2 adsorption, FTIR, Raman and TEM. The electrochemical properties of SMC electrodes were studied by constant current charge-discharge, cyclic voltammetry and electrochemical impedance spectroscopy. The results showed that the BET surface area, total pore volume and mesoporosity of prepared SMCs went through maximum as the crystallization time increased. At 24 h of the crystallization time, the BET surface area of obtained SMC (named SMCT-24) was as high as 1157 m(2) g(-1), and its total pore volume reached 0.97 cm(3) g, 95.0% of which belonged to mesopore. The specific capacitance of SMCT-24 capacitor was as high as 144 F g(-1) at the current density of 0.05 A g(-1 i)n 6 M KOH electrolyte, and remained at 127 F g(-1) after 1000 cycles, indicating that SMC could be a promising electrode material for electric double layer capacitor with high electrochemical performance. (C) 2014 Elsevier B.V. All rights reserved.