Learning media is important to support the teaching and learning process. With the existence of learning media in the form of a miniature protection system used for protection system courses. The limited learning media used in the practicum resulted in students having difficulty understanding the theory of the protection system without any help from modules/learning media. This study discusses the development of a miniature protection system using a Micom P127 relay on a 20 kV distribution system as a student learning medium. The method used in this study is the Research and Development method with the ADDIE model approach (Analysis, Design, Develop, Implement, and Evaluate). The results of the design and development of a miniature protection system consisting of an MV panel, Micom P127 relay, power meter, indicator lights, and other supporting components. The feasibility test for this miniature protection system shows a percentage of 85%, while the observation data tested by students and lecturers have a percentage of 75%. And from the results of the data on the increase in the ability of students as many as 20 people, there was an increase from 50% to 73%. So from the analysis, the miniature protection system using the Micom P127 relay has a GOOD category (B) so that it can be applied in learning protection system courses.