This study aims to determine the effect of the TGT (Teams Games Tournaments) cooperative learning model on students’ conceptual knowledge on momentum and impulse material in grade X 7th state Senior High School (SMA) in Medan City. The research type is a quasi-experiment with a two-group pretest-posttest design. The instrument used in this study was a test of students’ conceptual knowledge in the form of multiple choices and an assessment sheet to measure student skills and student activities. After the learning was given, the two classes carried out a post-test. The experimental class obtained an average value of 83.19 and for the control class, an average value of 64.58 was obtained. And student learning activities in the cooperative learning process type TGT (Teams Games Tournaments) in three meetings experienced an increase with an average value of 72.4 (active) meeting I, 77.22 (active) meeting II, 82, 4 (active). Based on the test results, it was found that the cooperative learning model type teams games tournament had a significant effect on students’ conceptual knowledge on momentum and impulse material in grade X 7th state SMA in Medan City.