Micro, Small and Medium Enterprises in Denpasar City still face low mastery of technology and financial management, one of which is the application of technology-based accounting information systems (e-commerce) for small and medium enterprises. The research objective was to determine the relationship between environmental uncertainty, trust and ease of information technology moderating behavior in accounting information systems. Research with a quantitative approach, the method used is multiple linear regression with moderated regression analysis. The study population was 816 small and medium enterprises. The sampling method technique was the incidental sampling approach and the Slovin formula so that a sampling of 100 small and medium enterprises that had used e-commerce was determined in the city of Denpasar. The results of research that have been conducted determine the relationship between user behavior in accounting information systems that affect individual performance, the relationship between environmental uncertainty affects accounting information systems mediated by individual performance, while the ease of information technology and its ability to be mediated by individual performance has an effect on the behavior of using accounting information systems. The application of accounting information systems in small and medium enterprises is expected to improve individual performance so as to increase income.