This study aims to determine the effect  of the Geogebra-assisted Think Pair Share type cooperative learning model on the understanding of mathematical concepts and student learning motivation. The data collection technique uses 5 essays on the ability to understand mathematical concepts and learning motivation questionnaires—data analysis with Data Normality Test, Data Homogeneity, t-Test, and Likert Scale Test. The results of (1) paired sample t-test tests in the experimental and control classes each obtained a calculated value < ttable so that H0 was rejected and H1 was accepted. (2) Independent test t-test samples in experimental class and control class obtain tcalculate values > ttable so that H0 is accepted and H1 is rejected. Moreover, (3) the results of student motivation questionnaires were obtained on average by 78% with solid criteria.