This study establishes a comparison approach for indexes between Vietnam and Taiwan, in order to determine the differences and similarities between indexes inside one country and with another. The study’s database consists of Vietnam and Taiwan’s statistical data of 8 years from 2006 to 2013. Base on the study’s method, it is expected to predict the trend with a higher than 80% correlation between indexes. Therefore, the proposed method can be a promising tool to assist decision makers in construction management. The empirical results of this study illustrate the relationships between construction and economic indicators between Vietnam and Taiwan. Base on the data collected it is possible to draw a short-term prediction of the Construction Cost Index and other indicators, which serves as a decent tool in public building cost estimations in Vietnam. Absolute number is not possible, however, for such a frequently high fluctuated but not yet technology familiar construction industry like Vietnam’s, this simple method is a decent approach to the Construction Cost Index forecasting study, which is still new in Vietnam.