The purpose of this study was to analyze the effect of financial performance on profit growth with firm size as a moderating variable in Islamic commercial banks for the 2016-2020 period. This research uses quantitative research by using multiple regression analysis and Moderated Regression Analysis (MRA) as data analysis. This study uses secondary data. The object of this research is Islamic banks in the period 2016 to 2020. The sample used in this study used a purposive sampling method, the research sample was adjusted to the agreed criteria as follows: 10 Islamic banks. The analytical tool used is the statistical application Eviews 9. The test results of the multiple linear regression method prove that the Quick Ratio (QR) variable, Debt to Equity Ratio (DER), Total Asset Turnover (TAT) has a negative and significant effect on profit growth, Net Profit Margin (NPM) has a positive and insignificant effect on profit growth while Return on Assets (ROA) has a positive and significant effect on profit growth. Meanwhile, testing the Moderated Regression Analysis (MRA) method proves that the company's bookkeeping (Z) is unable to moderate the relationship between Quick Ratio (QR), Debt to Equity Ratio (DER), Total Asset Turnover (TAT) and Return On Assets (ROA) to profit growth ( Y) and firm size (Z) are able to moderate the relationship between Net Profit Margin (NPM) and profit growth (Y).