This dissertation investigates the impact of the new underwriting policy - Competitive Auction Policy for conducting an initial listing on a Stock Exchange or Over-the-Counter market since 2016. This study examines whether the average bidding price of the Competitive Auction Policy is more effective than the offering price of the Book Building Policy. By using the Multiple regression analysis, it shows that the returns and excess returns of a stock would be affected by the underwriting policy. The Competitive Auction Policy has a negative impact on the first day returns and excess returns but has a positive impact on the net value of tangible assets. In addition, the discount rate of the offering price would be smaller than that of the Book Building Policy, which better reflects the intrinsic value of a stock.