This thesis explains and analyses the impact of macroeconomic factors on the price of shares in the HPB money market fund in the period from January 2007 to April 2017. The macroeconomic factors analysed in this thesis are: money supply, inflation and internal debt of the central government. The method of research was multiple regression analysis. HPB Invest is the investment fund owned by the Hrvatska Poštanska Banka. For the needs of this thesis, the author decided on the HPB money market fund because this fund has almost as a rule had average yield in relation to its competition for when it was founded, and thus is an exemplary example of an average money market fund operating on the Croatian financial market. Upon conducting the regression analyses, the conclusion was reached that the internal debt of the central government has the greatest and positive impact on the price of shares in the HPB money market fund, followed by inflation which also has a positive impact on the price of shares in the fund. The third macroeconomic factor, money supply, has a negative impact on the price of shares in the HPB money market fund. It may be concluded that the yield of a money market fund is not directly linked to the price of shares of a fund precisely due to its nature and the characteristics of a money market fund. The net asset value of funds (NAV) is calculated on a daily basis. By investing in a money market fund, a yield of little more than the interest paid on a savings account shall be achieved. The risk of a money market fund portfolio is minimal. Money market funds serve as a safe haven for funds that are invested for a short-term period that otherwise have an intended use of certain spending, such as payment of a specific invoice when its payment becomes due. Similarly, money market funds may serve as an accumulation of money for some long-term investment. In relation to the most recent financial crisis, the majority of investors allocated their funds and invested in less risky assets. The Croatian National Bank by creating interest rates, strongly impacted the formation of interest rates on the money market. The Ministry of Finance by issuing treasury notes has a great impact on the liquidity of money markets.