This study aims to determine the effect of the case study learning metode on tenth-grade students' learning outcomes of Geography subjects at SMA Negeri 1 Mangunjaya, Pangandaran Regency. The research method used in this study was a quasi-experiment with a Control Group Pretest and Posttest Design. The sample in this study was tenth-grade students of IPS (Social Education) 1 class as an experimental class with 21 students and tenth-grade of IPS 2 class as a control class with 21 students. The results showed that the case study learning metode significantly affected tenth-grade students' learning outcomes in Geography at SMA Negeri 1 Mangunjaya, Pangandaran Regency. This was based on the calculation results that there was a difference in the value of t-count and t-table, which were 4.036 and 2.093, respectively.