In decades, the growth of the productivities in the National Income based on the developments of information economy in their countries. Besides the high-tech industries and the Information and Communication Technologies (ICTs), the information related industries contributed the growth of Nation Income. This study intended to measure the size and the structure of the information economy in Taiwan. In order to recognize the trend and the difference of the information economies among our numerous countries, we choose Porat¡¦s (1977) studyas our framework. The proposes of this study list below: 1. Measuring the size and the structure of the information economy in Taiwan. 2. Proposing to improve the methodology on measuring the information economy, especially the parts about the data resource and the identification of the information occupations in Taiwan. 3. Finding the difference on the time series between Taiwan and other countries when we developed the information economy model and making the policy suggestions on it. Key Words: Information Economy, Input-Output Table, ICT, National Income Accounts, Value-added