In this paper, a Proton Exchange Membrane (PEM) fuel cell with new symmetrical flow channel pattern was designed and fabricated in-house. The fabricated PEM fuel cell has nominal power of 10 W, with an active area of 25 cm² and Nafion 117 membrane. Using a fuel cell test station, the effects of temperature and relative humidity on the performance of fabricated PEM fuel cell (i.e. voltage - current density curve) was examined. Laboratory results showed that fabricated PEM fuel cell is able to produce maximum power density of about 0.45 [Wcm^-2] or 11W power. A comprehensive three-dimensional, single phase and non-isothermal model is developed for the fabricated PEMFC. The presented model is a nine-layer model that consists of current collectors, flow channels, gas diffusion layers, catalysts layers at the anode and the cathode as well as the membrane. A commercial CFD software (Fluent) was used to solve the governing equation. Comparison of numerical and experimental results shows that there is a good agreement between them. The results indicate that the new flow pattern can produce uniform temperature, current density and concentration distributions over the PEM fuel cell active area.