Time-dependent measurements of pressure drop in different flow fields on the cathode of a PEM fuel cell with different operating conditions of mass flow rates and cell temperatures on current distribution were conducted. The results show that, among four flow fields studied herein, the interdigitated flow channel has the biggest pressure drop and least influence on current distribution at an early phase (<= 30 min) compared to those of the other three channels. In addition, the effect of pressure drop on water accumulation was noted. Similarly, the effects of mass flow rates as well as the cell temperature were also examined and discussed. (C) 2010 Elsevier Ltd. All rights reserved.