The parameter identification of a mathematical model of a molten carbonate fuel cell (MCFC) is presented. The model is spatially distributed in two dimensions and describes the strongly non-linear coupling of the temperature field and reactions inside a MCFC. It contains a high number of unknown parameters that need to be validated by experimental means. Therefore, measurements from an industrial fuel cell power plant are used. This validation approach requires an elaborate strategy, which is presented in detail. The resulting set of parameters can predict the behavior of the MCFC over a broad operating range with a very good precision. The validated model is an important basis for further process optimization and for control system design.