Abstract: The porous transport layer is an important component in the proton exchange membrane electrolysis hydrogen production system, which is related to the efficient transport of gas and water and the effective conduction of electrons. In this study, commercial titanium felt is etched with hydrochloric acid and oxalic acid, and acid-treated titanium felt with excellent electrochemical performance is obtained. The characterization of the surface morphology and elemental composition of the acid-treated titanium felt show that the acid treatment can effectively remove the oxide layer on the surface of the titanium felt, and will not affect the chemical properties and pore structure of the titanium felt. The contact resistance and electrochemical tests show that the contact resistance of the acid-treated titanium felt is effectively reduced, and the cell voltage of the electrolysis with acid-treated titanium felt is lower under the same current density. At the same time, due to the change of microstructure and wettability of titanium felt after acid treatment, the mass transfer process of acid-treated titanium felt is significantly optimized compared with ordinary titanium felt. The results show that the titanium felt treated with 10% oxalic acid at 80℃ for 20 min has the minimum polarization loss, which can effectively improve the operating efficiency of the electrolytic cell.