Penelitian ini bertujuan untuk mengetahui pengaruh model pembelajaran project-based learning terhadap kemampuan berpikir kritis dan kemampuan pemecahan masalah. Penelitian ini merupakan penelitian kuantitatif dengan jenis pendekaran quasi eksperimen. Populasi pada penelitian ini berjumlah 150 siswa. Sampel penelitian ini sebanyak 50 siswa, dimana kelas VIII-2 sebagai kelas eksperimen berjumlah 25 siswa dan kelas VIII-1 sebagai kelas kontrol berjumlah 25 siswa. Metode pengumpulan data dengan menggunakan nilai post-test. Teknik analisis data menggunakan uji normalitas, homogenitas serta hipotesis menggunakan uji t. Hasil hipotesis kemampuan berpikir kritis didapat jumlah, T-hitung > T-tabel yaitu 2,051942642 > 1,70814, sehingga H0 ditolak dan H1 diterima yang artinya terdapat pengaruh penggunaan model pembelajaran project-based learning terhadap kemampuan berpikir kritis siswa. Hasil hipotesis kemampuan pemecahan masalah didapat jumlah T-hitung < T-tabel, yaitu 1,690763525 > 1,677224196, sehingga H1 diterima, H0 ditolak yang artinya terdapat pengaruh penggunaan model pembelajaran project-based learning terhadap kemampuan pemecahan masalah. ABSTRACT This research aims to determine the effect of the project-based learning model on critical thinking abilities and problem-solving abilities. This research is quantitative research with a quasi-experimental approach. The population in this study was 150 students. The sample for this research was 50 students, where class VIII-2 as the experimental class had 25 students and class VIII-1 as the control class had 25 students. The data collection method uses posttest scores. Data analysis techniques use normality, homogeneity and hypothesis tests using the t test. The results of the critical thinking ability hypothesis were obtained by the number t_count> t_table, namely 2.051942642 > 1.70814, so that H_0 was rejected and H_1 was accepted, which means that there is an influence of the use of the project based learning model on students' critical thinking abilities. The results of the hypothesis of problem-solving ability were obtained by the number t_count < t_table, namely 1.690763525 > 1.677224196, so that H_1 was accepted, H_0 was rejected, which means that there is an influence of the use of the project-based learning model on problem solving ability.