This paper reports a nonlinear fuzzy modeling study of a molten carbonate fuel cell (MCFC) stack by an identification method. NICK is a complex nonlinear, multi-input and multi-output (MIMO) system that is hard to model by traditional methodologies. The Takagi-Sugeno (T-S) fuzzy model is suitable to model a large class of nonlinear MIMO system. In this paper, a MIMO T-S fuzzy model is used to represent MCFC. An identification method is used to determine both the nonlinear parameters of the antecedents and the linear parameters of the rules consequent in the T-S fuzzy model. The simulation tests reveal that obtained T-S fuzzy model using the identification method can efficiently approximate the static and dynamic behavior of a MCFC stack. Furthermore, based on this proposed T-S fuzzy model, valid control strategy studies such as predictive control, robust control can be developed. (c) 2007 Elsevier B.V. All rights reserved.