Lesson Study in an Inclusive Mathematics Classroom using Multicommunications Media: A Ring Theory Course. Objective: This study aims to describe learning ring theory courses by a lesson study using multicommunication media in inclusive classes of Muhammadiyah Makassar University. Methods: This study uses an experimental research design by analyzing and directly assisting students in learning. The analysis of this activity refers to plan, do, and see stages. The subjects in this study were students of the 2017 class of Muhammadiyah Makassar University, totaling 28 students, one of whom was a deaf student. Findings: The results show that at the beginning of the performance of lesson study without video, deaf students were still less actively involved in discussing with their group friends, while in the performance of learning using multi communication media, namely in the form of learning videos accompanied by running text and sign language, deaf students seemed more active than previous learning without video media. Conclusion: It is concluded that the use of multi-communication media through the implementation of lesson study has a positive impact on learning and helps students understand the material, especially students who are deaf.