One of the most important challenges faced by SOFC technology towards the commercialisation lies in the issues related to scale up. In this work, root cause analysis of performance loss in scaled up (1:50) SOFC is carried out. Reduction in actual contact area (6.7% on cathode and 2.5% on the anode) between the metallic interconnects and the cell, and nonuniformity of reactant distribution, are found to play critical roles towards the poor performance of the scaled up cell. Finally, suggestions are made to sustain the performance during the scale up. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.