The use of learning websites in the field of education has now become a necessity. One of them is using a Learning Management System that supports the learning process. The Learning Management System is a system that tertiary institutions widely use to help the teaching and learning process run smoothly. Apart from providing benefits to tertiary institutions, this system must also be well received by the primary users, namely students. To assess the performance of a Learning Management System, tools that can be used include the Analysis using the Index – Performance Matrix. This matrix was initially developed to assess consumer satisfaction with the marketing of goods or services. Still, it can be developed to assess user satisfaction with the services of an LMS website. This study tries to assess one LMS using indicators to assess website user satisfaction, using the Importance – Performance Analysis Matrix, which is modified according to website assessment standards. The results of this Analysis obtained data on the gap between the performance expected by the user and the user's preferences regarding the level of importance of each indicator. Based on the data spread over the four quadrants, it can be determined which factors should be prioritized for improvement or improvement. These variables are variables 2, 3, 4 and 6, namely the Application features , application reliability, replication suitability and also ease of repair, we found several variables that need to be fixed immediately and which factors are not yet urgent. This research was conducted at a university in South Tangerang.