We have investigated the transient behavior of the water transport across the membrane of the PEM fuel cell to seek- for effective control schemes so that the best dynamic performance of the fuel cell can be obtained. It is found that both a larger starting operational current density i(0) and a smaller operational current density i can lead to a smaller dynamic response time t(ss), the time for the water distribution across the membrane to reach the steady state. Present results nevertheless point out that the most powerful as well as the most feasible control scheme. is to control the humidification parameter k, i.e. to adjust the water content of the feeding fuel. so that the t(ss) would remain steadily in a reasonably low value in a wide range of water flux fraction beta, another control parameter of the membrane. The present conclusion can be useful for the design of the PEM fuel cell when its application on the dynamic mobile system is concerned. (C) 2004 Elsevier B.V. All rights reserved.