The purpose of this research was to analyze the effect of cooperative learning method toward the seventh-grade students of Private Junior High School in South Tangerang. The method that used in the research was an experimental method, where the independent variable was cooperative learning method and the dependent variable was the result of learning mathematics. The sample was taken by using the random sampling technique. The test data requirements were done by using the following formula: chi-square test for normality test and Fisher test for homogeneity test. The hypothesis submission was done using t-test. The result of the research shows that there are significant effects of cooperative learning method toward students' mathematics learning result especially on the plane figure subject on the seventh-grade students of the private junior high school in South Tangerang.