In this paper, model order reduction (MOR) of cascade-type polymer electrolyte membrane (PEM) fuel cell stack with integrated humidifiers and water separators is investigated. The purpose of this work is to attain orders of magnitude improvement in numerical simulation speed. Both the anode and the cathode of stack operate in a dead-end mode. The reduced-order model (ROM) is developed for continuous and discrete form of the cascade-type PEM fuel cell models. The obtained ROM is verified with the full nonlinear model, which full-order model itself is validated using experimental data from cascade-type 4-cells PEM fuel cell stack. Responses of different orders of ROMs are compared to those of full-order model to determine the minimum order of the model that approximates the behavior of the original model properly. The results predicted by the developed reduced-order model nearly follow the full nonlinear model and experimental results. According to the low computational cost of ROM, the derived model can be further used for real-time control and diagnostic applications. (C) 2016 Elsevier Ltd. All rights reserved.