It is investigated on the relationship between cell performance and the hydrophobisity of gas diffusion layer. The cell performance is significantly affected for PTFE content of carbon cloth at high current density. This results mean that the hydrophobisity of gas diffusion layer related to water transport and the diffusion of reactant gas from gas diffusion layer to catalytic layer. At the small amount of PTFE in gas diffusion layer, water could transport easily to catalytic layer, but couldn`t remove easily water. The large amount of PTFE is a contrast to it. At high current density, water transport in or out electrode is directly related to the cell performance because of gas diffusion, electric conductivity and the humidification of polymer electrolyte.