A direct ethanol fuel cell (DEFC) of 5 cm(2) membrane-electrode area was studied systematically by varying the catalyst loading, ethanol concentration, temperature and different Pt based electro-catalysts (Pt-Ru/C, Pt-black High Surface Area (HSA) and Pt/C). A combination of 2 M ethanol at the anode, pure oxygen at the cathode, 1 mg cm(-2) of Pt-Ru/C (40%:20%) as the anode and 1 mg cm(-2) of Pt-black as the cathode gave a maximum open circuit voltage (OCV) of 0.815 V, a short circuit current density of 27.90 mA cm(-2) and a power density of 10.3 mW cm(-2). The optimum temperatures of the anode and cathode were determined as 90 degrees C and 60 degrees C, respectively. The power density increased with increase in ethanol concentration and catalyst loading at the anode and cathode. However, the power density decreased slightly beyond 2 M ethanol concentration and 1 mg cm(-2) catalyst loading at the anode and cathode. These results were validated using cyclic voltammetry at single electrodes under similar conditions to those of the DEFC.