Stock market index plays an important role as a measure of development of stock markets ofa country or a region. Results of this empirical research show that in its 13 years of development, Vietnamese stock market indexes only had limited values because of their poor market representation and predicting power, and the need to merge Hanoi and HCMC stock exchanges. The research suggests a new set of stock market indexes to deal with shortcomings of existing indexes, thereby providing relevant entities with a new view on development of stock market in Vietnam.