A capital market is a financial market in which long-term debt (over a year) or equity-backed securities are bought and sold (Sheffrin, 2003). Capital market plays an important role in mobilizing resources, and diverting them in productive channels. Investment Corporation of Bangladesh (ICB) acts as an Investment Banker, Market maker & Portfolio Manager which has significant contribution from the beginning of its establishment to develop a well-organized, vibrant, balanced, efficient, stable and liquid capital market in Bangladesh. The functions of ICB are very much related to the development of the capital market in Bangladesh. However, the existing literatures are not adequate to show the role of investment banks in the development of capital market of Bangladesh. So, this indicates to the research problem which motivated the endeavor to undertake research on the role of ICB in the development of capital market of Bangladesh. Secondary data of FY2008-2009 to FY2016-2017 have been used to achieve the research objective and collected data have been analyzed through multiple regression and correlation. The paper found that ICB provides institutional support to meet the equity gap of the companies and in view of the national policy of accelerating the rate of savings and investment to foster self-reliant economy, ICB assumes an indispensable and trustworthy role. So, the paper recommends that the number of IPOs issued by ICB is decreased with the total IPO issued in capital market and the performance of ICB mutual funds are decreasing year to year which are needed to improve.