Abstract: Parts in compressors sometimes is deformed with time going.Therefore it is very important to monitor the deformation and predicate the trend to keep the performance of the compressors.In this paper，the base theories for time series predication model are introduced here.Parameter identification methods are also used.Based on the deformation data of muffle plate in compressor，a predication model for this part is established to monitor and forecast the deformation.Practical applications show that the model in this paper is reliable and useful.