In the history of fuel cell development, its performance is always influenced by the water behavior in flow channel blocks. The position of water behavior and moisture directly affects the efficiency of the fuel cell. If the flow channel block of cathode collects much of the water behavior, that fuel can not diffuse easily. Moreover, in case of high fuel flow rate or excess heat in high ampere, the membrane electrode assembly becomes dry and deteriorates the performance of fuel cell. The objective of this experiment is to observe and study the relationship between water behavior of cathode and the performance of the fuel cell in transparent PEMFC when the fuel cell consumes difference of voltage and temperature. And we also hope to provide a method to study and solve the problems in water and heat management. The method we adopt in this experiment is to firstly fix the component of the fuel cell, and to fabricate them with Ion Power’s membrane electrode assembly、gold-coated brass and two-channel serpentine current collect plate、Plexiglas end plant. The status of this step is then confirmed and stabilized by constructing、testing、activation process. Finally, by operating the transparent fuel cell in steady mode of constant current、constant anode flow rate for a long time with the difference of voltage and temperature, we try to observe the water flooding behavior in cathode channel flow as well as to analyze the relationship between the water behavior and the property of power, voltage, ohmage.