The design of open-cathode polymer electrolyte fuel cells (PEFC) stacks with forced-convection requires a careful consideration on the geometrical and operating conditions as well as the characteristic of PEFC stacks and fan used. The operating point should be located at the intersection point between the fan and the stack characteristic curve. This paper evaluates the effect of key parameters and operating conditions on the system characteristic and stack performance of forced convection PEFC by utilizing computational fluid dynamic approach and Taguchi statistical method. A validated three dimensional open-cathode PEFC stack model with fan and immediate ambient were employed together with an L27 orthogonal array (OA) of Taguchi matrix of six factors and three level designs to determine the optimum combination of parameters as well as their interactions. The result indicates that fuel cell length plays important role on determining the fuel cell performance in term of current density and net power. Optimum combination of design and operating parameters were obtained with the objective function of maximizing net power generated by stack by taking into account the parasitic loads. © 2015 Published by Elsevier Ltd.