Penelitian dilaksanakan di salah satu SMP yang berada di Bandung. Penelitian ini dilakukan kepada siswa kelas VIII A sebagai kelas eksperimen dan kelas VIII D sebagai kelas kontrol. Tujuan penelitian ini meningkatkan kemampuan berpikir reflektif matematis siswa melalui model pembelajaran Connected Mathematics Project (CMP), karena berpikir reflektif merupakan hal penting yang akan dibutuhkan siswa dalam proses belajar, namun faktanya kemampuan berpikir siswa masih rendah. Metode penelitian yang dipilih yaitu kuasi eksperimen. Hasil penelitian ini diperoleh bahwa kemampuan berpikir reflektif matematis siswa yang melalui model pembelajaran Connected Mathematics Project (CMP) mengalami peningkatan yang termasuk dalam kategori sedang, kemampuan berpikir reflektif matematis siswa yang melalui model pembelajaran konvensional (ekspositori) mengalami peningkatan yang termasuk dalam kategori sedang, peningkatan kemampuan berpikir reflektif matematis siswa yang melalui model pembelajaran Connected Mathematics Project (CMP) lebih baik secara signifikan dibandingkan siswa yang melalui model pembelajaran konvensional (ekspositori), respon siswa terhadap model pembelajaran Connected Mathematics Project (CMP) dalam meningkatkan kemampuan berpikir reflektif matematis siswa memberikan respon positif yang lebih tinggi daripada respon negatif. The research was carried out at one of the junior high schools in Bandung. This research was conducted on students in class VIII A as the experimental class and class VIII D as the control class. The aim of this research is to improve students' mathematical reflective thinking skills through the Connected Mathematics Project (CMP) learning model, because reflective thinking is an important thing that students will need in the learning process, but in fact students’ thinking abilities are still low. The research method chosen was quasi-experimental. The results of this research showed that the mathematical reflective thinking ability of students who went through the Connected Mathematics Project (CMP) learning model experienced an increase which was included in the moderate category, the mathematical reflective thinking ability of students who went through the conventional (expository) learning model experienced an increase which was included in the moderate category, an increase The mathematical reflective thinking ability of students who go through the Connected Mathematics Project (CMP) learning model is significantly better than students who go through the conventional (expository) learning model. positive responses are higher than negative responses.