Abstract: Anomaly Filtering Model (AFM).developed originally by Chinese meteorologists, possessed its own unique advantage, as a long-range weather forecasting model. Based on the idea, a multi-level, primitive equation anomaly spectral model of global atmosphere has been designed, and by the model, atmospheric response to the tropical SST anomaly has also been experimentally simulated. It is shown that the model is different from both the AFM and the GCM, and also displays an extensive applied value in study or in prediction of short-term climatic anomaly.