The aim of this study is to find out how great the influence of Underwriter Reputation, Company Age, Return on Asset (ROA), and Financial Leverage (DER) on the rate of Underpricing of Shares listed on the Indonesian Stock Exchange at the time of Initial Public Offering (IPO) in the period 2019-2021. To test this, the researchers used quantitative methods with secondary data collection techniques such as prospectus reports and corporate finances as well as literature studies. Analysis techniques used using E-views version 9. The results of research and discussion found that Reputation Underwrite, Return on Asset, and Financial Leverage did not affect the rate of Underpricing of Shares, whereas Age of the Company had an influence. So together the four Independent variables only affect the dependent variable by 12.44 percent.