Vietnam’s stock market although has small scale without a long history of development but the exchange has just started for a massive development. There have also been a number of anomalies, suggested that the market is not efficient. Therefore, there is a possibility that active investors with right strategy can consistently achieve higher profit than the market portfolio. This paper analyzes the statistical and economic significance of the calendar anomalies to propose appropriate strategies or recommendations. Studying the calendar anomalies in Vietnam also diversifies the research scope and validates some hypotheses in the past. In this research, the authors just analyze the monthly effects and the experimental results of this study may have significant implications not only for financial managers, financial advisers and investors but also for government to implement policy on stock market.