Interactive Parameter Estimator (IPE) is an interface to facilitate the implementation of the Fuzzy State SpaceAlgorithm that addresses inverse problems in multivariable control systems directly; compared to repeated simulation of forward problems. The algorithm is the main feature in the development of Fuzzy State Space Model (FSSM), which was developed to cope with the demand and performance due to the increasing system complexity. To take advantage of the effectiveness and some distinguish features of the algorithm, it is important to develop an efficient computational tool for ease of implementation. Therefore, this paper describes the development of IPE of a superheater system using Visual Basic programming tool. Besides providing an efficient computation for estimating the optimal combination of the parameters, IPE is an innovative tool for industrial applications.