本文嚐試以投入產出(inputi-output)分析，以建立一套開放體系下的加值稅的物價理論。企圖瞭解臺灣以加值稅代替部份貨物稅、營業稅及與營業額有關的印花稅，所可能造成的物價效果。 根據本文的理論分析，得到一些重要結論。1.在相等稅收的條件下，實施加值稅必要來各業物價的變動，因此吾人關心的應是物價變動的正負與高低，而非物價變動的有無。2.稅制改變前的宣導工作是物價變動高低的關鍵因素之一。一旦價格僵固性存在，則稅制改變更加強物價上漲的力量。

The purpose of this study is to employ the input-output analysis in building a price theory on value added tax in an open economy with aims to better understand the price effects by adopting such a tax partially substitute commodity tax, business tax and business-volume-related stamp duty. Some of the important findings revealed by this analytical approach are as follows: 1. With assumption of a given tax revenue, the adoption of value added tax will inevitably bring about changes in prices of various industries, and thus our major concerns should place on the extent of ups and downs of such changes, instead if there is a correlation between such a tax and price level. 2. One of the key elements in effecting the extent of price changes appears to be the activities of promotion so as not to arouse unnecessary panic among business community before adopting value added tax system. 3. The study also suggested that once the price rigidity prevails, such a change in tax system will further accentuate the surge in price in general.