Additive manufacturing (AM) technology is capable of fast and low-cost prototyping from complex 3D digital models. To take advantage of this technology, a stainless steel (SS) plate with parallel flow field served as a combination of a cathode bipolar plate and a current distributor; it was fabricated using selective laser melting (SLM) techniques and investigated in a proton exchange membrane electrolyzer cell (PEMEC) in-situ for the first time. The experimental results show that the PEMEC with an AM SS cathode bipolar plate can achieve an excellent performance for hydrogen production for a voltage of 1.779 V and a current density of 2.0 A/cm(2). The AM SS cathode bipolar plate was also characterized by SEM and EDS, and the results show a uniform elemental distribution across the plate with very limited oxidization. This research demonstrates that AM method could be a route to aid cost-effective and rapid development of PEMECs. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.