The success of an educational organization depends on access to relevant and up-to-date information. The administration management of an institution will determine the quality of education, where the available information is obtained from good academic activities. This research aims to improve the effectiveness of academic management by implementing a web-based academic management information system, providing optimal services in planning, implementation, and efficient evaluation at SMA Negeri 9 Banda Aceh. This research employs a quantitative method using a one-group pretest-posttest design. Data were collected through interviews, observations, and surveys. The research was conducted at SMA Negeri 9 Banda Aceh, with a sample size of 54 teachers and 258 students. The results of the research show that the planning, implementation, and evaluation of the web-based academic management system are functioning well and can improve academic management effectiveness, with an N-Gain Score value of 65,68%, categorized as effective.