The background of this research is the importance of students' mathematical understanding abilities, but from several studies, it has been shown that the lack of mathematical understanding abilities is caused by a lack of learning media that constructs students' knowledge, one of which is the use of student worksheets which only contain material and practice routine questions. The learning context can be built through various things that are close to students, one of which is sports. Therefore, this study will use futsal as a means of learning mathematics context. This study aimed to determine students' mathematical understanding skills in number operations learning activities using learning media in the context of futsal. This study used a quasi-experimental method with the non-equivalent control group design involving control and experimental classes at one of the junior high schools in Kabupaten Karawang. The instrument used was a test of mathematical understanding ability in which the data was processed in the form of descriptive statistics to see the difference in the average scores of the two classes. The results of the increase in the average value of students who use learning media in the futsal context are greater than the average value of students who do not use learning media in the futsal context in material for number operations. The mathematics learning media used in this study can be implied by being used as a learning media in the futsal context in number operations material to improve students' mathematical understanding abilities in learning mathematics.