本文利用馬可夫轉換模型研究美國、日本、台灣及南韓等四個國家，針對影響經濟成長率之多項重要總體變數作進一步的實證，並同時將貨幣供給變動率區分為預期及非預期的貨幣政策，作為分析其對經濟成長的影響是否存在不同的效果。實證結果顯示日本、台灣與南韓的經濟成長率與預期貨幣政策有正向關係，但美國則不存在顯著關係；而日本、台灣與南韓的未預期貨幣政策與經濟成長率為正向關係，其有效性大於預期的貨幣政策效果。在其餘總體經濟變數部分，政府調整重貼現率之宣示效果大於實質的意義，而通貨膨脹率及失業率與經濟成長率多成負向關係。綜論之，央行政策的實施對經濟成長率之影響，台灣與美國情形一致，而日本與南韓則較為相似。貨幣政策的施行確實對於經濟體系中其他實質變數存在一定程度的影響，政府在政策之擬定上應不可忽略其可能產生的抵換效果。 This paper exams the relationship among economic growth rate and macroeconomic variables using Markov switching model in the U.S., Japan, Taiwan and South Korea. We also divide the monetary policy into expected and unexpected policy for analyzing the different impacts to economic growth rate. The empirical results show the positive relationship between expected monetary policy and economic growth rate in Japan, Taiwan and South Korea. However, the relationship does not exist in the U.S. Moreover, the relationship between unexpected monetary policy and economic growth rate is positive in Japan, Taiwan and South Korea. The effect of unexpected monetary policy is significant than expected ones. Further, the declare effect of adjusting discount rate by the government is significantly then the real effect. The relationship between economic growth rate and inflation or unemployment rate are negative. In conclusion, the implementation of the Central Bank policy influence on economic growth rate, Taiwan keeps the same with U.S.''s situation, comparatively similar in Japan and South Korea. The monetary policy will affect the other real variables in economic system, and the government should not omit the trade off effect.