The flow field structure has important effect on the flow characteristics and cell efficiency. In order to investigate spatial distribution of local gas flow field, species concentration and local current density in the PEI\TFC with multi-channel serpentine flow field, a steady three-dimensional mathematical CFD based model presented in the author's previous paper is applied to conduct numerical study on a small-scaled single proton exchange membrane fuel cell (the electrode active area 5.9*6.1 cm(2)) in this paper. Based on the model, distribution of species concentration, fluid flow, local current density and pressure are computed. The flow characteristics and transport mechanism is discussed and analyzed. It indicates that current density is relatively uniform with this design, and cell can offer promise good performance.