Here we report the effect of anode microstructure on the SOFC performance using two types of micro tubular SOFCs, 0.8 and 1.6mm in diameter with different anode microstructure (Cells A and B). The cells consisted of NiO-Gd doped ceria (GDC) as an anode (support tube), GDC as an electrolyte and (La, Sr)(Fe, CO)O-3 (LSCF)-GIDC as a cathode. The anode tube for Cell A was prepared using NiO (d(g) similar to 5 mu m) and GDC (d(g) similar to 0.2 mu m) powders without using a pore former, while the anode tube for Cell B was prepared using NiO (d(g) similar to 0.5 mu m) and GDC(d(g) similar to 0.2 mu m) powders using a pore former. The peak power density of these cells were shown to be 203, 400 and 857mW cm(-2) for Cell A and 273, 628 and 1017mW cm(-2) for Cell B, respectively at 450, 500. and 550 degrees C operating temperature. Both cells showed outstanding performance, and furthermore the anode microstructure of Cell B was shown to be more optimized for better cell performance. (C) 2008 Elsevier B.V. All rights reserved.