Understanding of current and temperature distributions along with the variation of gas composition in the cell of PEMFC is crucial for designing cell components such as the flow field plate and the membrane-electrode assembly. Current distribution in the single cell was experimentally measured by using a specially designed single cell which was composed of 81 compartments. Each compartment was electronically insulated from the neighboring compartments. Current distribution was measured by using Hall effect sensors that were connected to the corresponding compartments. The influences of flooding and stoichiometry variation of the feed gas were discussed in terms of the rate of electrochemical reaction, from the measured distributions of local currents in a segmented single cell. (C) 2003 Elsevier Science B.V. All rights reserved.