The purpose of this study is to analyze the determinants or factors that determine the decision to invest in Islamic Mutual Funds through online platforms, using the Theory of Planned Behavior (TPB). This study measures one dependent variable, namely the decision to invest in Islamic Mutual Funds through online platforms and six independent variables, namely Islamic financial literacy, Islamic mutual fund investment literacy, benefit perception, technological advancement, investment risk and investment return. The research is quantitative in nature, using primary data. Data collection was conducted with the dissemination of questionnaires to respondents in Greater Jakarta Area who have accessed online platforms to invest in Islamic Mutual Funds. This study then uses SEM-PLS (Structural Equation Modeling-Partial least Square) analysis with SmartPLS software to analyze the data. The study shows that Islamic Financial Literacy and Investment Literacy of Islamic Mutual Funds have a negative and significant influence on the decision to invest in Islamic Mutual Funds Online. While the variables of perception of benefits, technological advances, investment risk and investment return have no influence on the decision to invest in Islamic Mutual Funds Online. Thus, the better the level of literacy or understanding of Islamic finance and the investment literacy of Islamic mutual funds, the more people's decisions to invest in sharia-compliant mutual funds through online platforms.