The 21st century is marked by the use of technology in learning. One example is the use of smartphones as learning media in the form of Mobile Learning Modules, which are expected to make it easier for students to learn biology material. This study aims to develop biology learning media in the form of Android-based Mobile Learning Modules on the Immune System material. The research method used is Research and Development (R&D). Research procedures include concepts, design, material collection, product manufacture, product testing, and distribution. The study was conducted at MAN 9 Jakarta. The research involved media experts, material experts, students, and biology teachers. Data analysis using Kolmogorov Smirnov, statistical tests using Paired Sample t-Test. The results showed that the Android-based Mobile Learning Module for the Immune System material was rated by an average score of 91.4%. The average pretest and post-test scores were 57 and 78.8. The conclusion of this study shows that this Android-based Mobile Learning Module has fulfilled the requirements as a learning medium and can improve student learning outcomes on the Immune System material.