This purpose of the research is to analyze the influence of expense ratio, mutual fund, size and turnover ratio on the performance of stock mutual funds registered with the Financial Services Authority (OJK) for the 2017-2022 period. The performance of stock mutual funds is measured by comparing the mutual fund returns minus the risk free rate with the mutual fund standard deviation. Expense ratio is measured by dividing total operational costs by net asset value, and the mutual fund size variable is measured using the natural logarithm of the net asset value of stock mutual funds. And the turnover ratio is measured by comparing the percentage of sales or purchases with the net asset value of stock mutual funds. This research uses secondary data obtained through the Financial Services Authority website and the fund market website. The sampling method used purposive sampling and obtained 184 stock mutual funds. The data was analyzed using panel data regression which was processed using eviews version 10. The research results showed that the turnover ratio had a positive and significant effect on the performance of stock mutual funds. Meanwhile, the expense ratio variables and the size of stock mutual funds have no effect on the performance of stock mutual funds registered with the Financial Services Authority.