The performance of high-temperature PEM fuel cell (HT-PEMFC) is substantially influenced by physical parameters. In this work, the effects of three parameters on the performance of HT-PEMFC are studied by using a 3D model in COMSOL. The parameters are the operating temperature, membranes thickness and catalyst layer's thickness. The polarization curves are adopted to analyze the effects on the performance. The results show that the increase of temperature can enhance the performance of fuel cell. For the effect of catalyst layer thickness, the cell performance is promoted as the catalyst layer's thickness decreases. For the effect of the thickness of membrane, it is found that the thinner membrane of fuel cell can achieve better performance. These findings can be further extended to guide the operation and design of HT-PEMFC in practical applications. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.