Penelitian ini bertujuan untuk mengkaji pengaruh model pembelajaran Problem Based Learning (PBL) terhadap keterampilan berpikir kritis siswa kelas X pada mata pelajaran Geografi di sekolah menengah atas Islam Diponegoro Wagir. Penelitian menggunakan pendekatan kuantitatif dengan metode eksperimen semu melalui desain Nonequivalent Control Group Design yang melibatkan pemberian pre-test dan post-test pada kelompok eksperimen dan kontrol. Data dikumpulkan melalui observasi, dokumentasi, dan tes esai yang telah diuji validitas serta reliabilitasnya. Analisis data dilakukan menggunakan uji normalitas, uji homogenitas, dan uji hipotesis dengan independent sample t-test. Hasil analisis menunjukkan nilai signifikansi 0,000 (< 0,05), yang menandakan adanya pengaruh signifikan penerapan PBL terhadap peningkatan keterampilan berpikir kritis siswa. Temuan ini menegaskan efektivitas PBL dalam mendorong kemampuan berpikir tingkat tinggi melalui pembelajaran berbasis pemecahan masalah. Kebaruan penelitian ini terletak pada penguatan bukti empiris penerapan PBL dalam pembelajaran Geografi di tingkat sekolah menengah atas. Implikasi penelitian menunjukkan bahwa PBL dapat dijadikan alternatif strategis untuk meningkatkan kualitas pembelajaran yang berorientasi pada keterlibatan aktif siswa. The effect of problem-based learning on geography students' critical thinking skills This study aims to examine the effect of the Problem-Based Learning model on the critical thinking skills of Year 10 students in Geography at Diponegoro Wagir Islamic Senior High School. A quantitative approach was employed using a quasi-experimental method with a Nonequivalent Control Group Design, involving the administration of pre-tests and post-tests to both experimental and control groups. Data were collected through observation, documentation, and essay tests that had been validated and tested for reliability. Data analysis comprised normality testing, homogeneity testing, and hypothesis testing using an independent samples t-test. The results revealed a significance value of 0.000 (p < 0.05), indicating a statistically significant effect of the PBL model on students’ critical thinking skills. These findings confirm the effectiveness of PBL in fostering higher-order thinking through problem-oriented learning activities. The novelty of this study lies in strengthening empirical evidence for the application of PBL in Geography instruction at the senior high school level. The implications suggest that PBL can serve as a strategic alternative for improving learning quality through enhanced student engagement.