This study aims to determine the effect of interest rates, inflation and market risk on the performance of stock mutual funds with a stock index of lq45 as the moderating variable. The independent variable in this case is the interest rate (x1), inflation (x2), market risk (x3) and the dependent variable is the performance of stock mutual funds (y) and the stock index lq45 as the intervening variable (m). The type of research used is associative research, with a quantitative approach. This study takes all time series data that converts interest rates, inflation and market risk, stock index lq45 and the performance of stock mutual fund for the period 2016 to 2019. The number of research samples using saturated sampling techniques obtained is 40 samples. Data analysis used multiple regression analysis and moderated regression analysis using spss23. The results of the F test show that the lq45 index is able to moderate the independent variable interest rate, inflation, market risk together on the performance of stock mutual funds. The t test results show that the stock index lq45 is able to moderate the relationship between the variable interest rate and market risk on the performance of stock mutual funds, while the inflation variable cannot be moderated by the stock index lq45 on the performance of stock mutual funds.