Mind Map is a learning concept that helps teachers in carrying out mathematics learning in the spatial construction material that is taught by trying to maximize the active role of students, especially knowledge that is applied and how it is applied in everyday life. With this concept, learning outcomes are expected to be more meaningful for students. The learning process takes place naturally in the form of student activities working and experiencing, not transferring knowledge from teacher to student. The quality of learning is more important than results. The purpose of this classroom action research (CAR) is to improve mathematics learning outcomes using the Mind Map learning method for class IX.1 students of SMP Negeri 1 Keruak in the 2020/2021 school year. In class action research (CAR) which was carried out in 2 cycles, from the results of the actions taken it was proven to be able to increase student learning mastery classically, namely in the first cycle by 62%, it could increase to 95% in the second cycle. The results of this classroom action research indicate that learning by applying the Mind Map method can improve the quality of learning and student learning completeness in mathematics subjects with completeness reaching 95%.