AbstractThe ability of synthesis is an ability to integrate parts or elements logically, so that it is transformed into a new structural pattern or form. The low ability of student synthesis will affect student learning outcomes. One alternative that can be used in mathematics learning is the AIR learning model (Auditory, Intellectually, Repetition). The AIR Model is a model where the teacher as a facilitator and students are active in using their senses to build their own knowledge. This study aims to find out how the ability of the synthesis of students in learning mathematics through the AIR learning model in SMA Negeri 3 Kejuruan Muda. The method used in this research is descriptive qualitative method. In this study, the population was all students of class X MIA in State Vocational High School 3, totaling 78 students. The sample in this study was taken randomly, which is class X MIA1, amounting to 25 students. The instrument used in this study took the form of tests and interviews. Based on the results of the data obtained that the average value of the pretest was 33.16, and the average value of the percentage of students' synthesis abilities was 10.67%. While the average posttest score was 60.16, and the average value of the percentage of students' synthesis abilities was 61.33%. So it can be concluded that the synthesis ability of students in class X MIA 1 of SMA 3 Vocational Youth before using using the AIR (Auditory Intellectually Repetition) learning model is classified in the low category but after using the AIR learning model (Auditory Intellectually Repetition) there is an increase that is classified in the medium category . Keywords: Synthesis Ability, AIR Learning (Auditory, Intellectually, Repetition)