Abstract: A structural decentralized predictor for. the chain system is presented. The only structural information required in the design of a tub-predictor is the model of the related subsystem, without taking into account of the structural information of other subsystems. The measured information in the sub-predictor is also decentralized. In addition to the input and output of the subsystem, it contains only the directly connected measures. The concepts of on-time prediction and super-time prediction are introduced, and some of their properties are studied. Finally, its application to a process control is discussed.