The research that has been carried out is entitled "The Effectiveness of MIKiR Active Learning in Class V Indonesian Language Lessons at MIS Mutiara Sei Mencirim". This research aims to determine the implementation of MIKiR active learning in class V Indonesian language lessons at MIS Mutiara Sei Mencirim, the effectiveness of MIKiR active learning applied in class V Indonesian language lessons at MIS Mutiara Sei Mencirim, and factors that support and hinder the implementation of MIKiR active learning in lessons. Indonesian language class V MIS Mutiara Sei Mencirim. This research is a qualitative research with a case study type of research. The subjects of this study were teachers and fifth grade students. Data collection was taken through interviews, observation, documentation and questionnaires. The author takes the role of a direct interviewer to dig up more complete data for teachers and students. The results of this research show that the implementation of MIKiR active learning in Indonesian language lessons can be proven from the learning outcomes which consist of Experiencing, Interaction, Communication and Reflection. In the "Experiencing" activity the teacher involves the students' five senses to understand the concepts of the material presented so that it is easier to understand, "Interaction" the teacher encourages students to be able to express ideas and reflect on themselves so that it also supports good understanding of the concept, "Communication" the teacher motivates the participants students to be brave and fluent in conveying ideas, and teacher "Reflection" creates an attitude in students to be willing to accept criticism and improve themselves, both ideas, work results and attitudes. MIKiR's active learning is very effectively applied to Indonesian language lessons for class V MIS Mutiara Sei Mencirim, as evidenced by the fact that during the learning process students always feel excited and happy, initially students still feel shy in asking questions or expressing their opinions, but often MIKiR's active learning this is applied at MIS Mutiara Sei Mencirim they don't feel boredom, in this case active learning MIKiR is very effectively used in Indonesian language lessons for class V MIS Mutiara Sei Mencirim. supporting factors in the application of MIKiR active learning, namely the teacher's role in this learning activity is very important because teacher creativity determines the learning process using MIKiR active learning and students will become the main character or role in each lesson, the teacher only needs to direct students in the learning process and students will show their respective creativity, and the inhibiting factor in the application of active learning MIKiR is the allocation of learning time that is not in accordance with the material because during the discussion process students who do not understand will tend to ask a lot of questions in order to be able to complete their group assignments.