Water electrolyzers that use an anion exchange membrane (AEM) are expected to be new devices for hydrogen (H-2) production that achieve high performance at low capital cost. Such an AEM electrolyzer could produce pressurized H-2 as easily as does as a proton exchange membrane (PEM) electrolyzer. In this study, H-2 pressure in an AEM electrolyzer was increased to 8.5 bars in the cell. Here, the effect of such high H-2 pressure on electrolysis performance was verified by simultaneously measuring the dependency of several parameters on current density during pressurized operation; parameters such as cell voltage, cell resistance, H-2 content in the anode gas, H-2 production rate, and water content in the produced H-2. Results also revealed that pressurized operation of AEM electrolysis offered the advantage of low humidity H-2 production, with minimal degradation in the electrolysis performance. (c) 2018 Elsevier Ltd. All rights reserved.