This study was motivated by the dominance of teacher-centered, one-way history learning patterns, which tend to make students passive and limit their ability to develop reflective thinking skills. To overcome this problem, the Culturally Responsive Teaching (CRT) approach is seen as a relevant alternative because it emphasizes the connection between teaching materials and students' cultural backgrounds and experiences. This study aims to analyze the effect of CRT implementation on students' reflective thinking skills in learning about historical relics from the Islamic period in Indonesia. The research design used was a quasi-experiment with a non-equivalent control group design model. The research subjects consisted of two classes, namely the experimental class that received learning with the CRT approach and the control class that used the Teacher Centered Learning (TCL) approach. The research instruments included a reflective thinking ability test and a student response questionnaire. Data analysis was conducted through prerequisite tests, Independent Sample T-Tests, and Effect Size calculations using Cohen's D formula. The results showed that student responses to the application of CRT were positive. The t-test produced a significance value of 0.000 < 0.05, indicating a significant difference between the experimental class and the control class. The Effect Size value of 0.97 was in the moderate category. Thus, the application of the CRT approach was proven to have a real effect on improving students' reflective thinking skills, where students were better able to understand the material, evaluate it, and form new experiences in formulating solutions based on their own understanding. ABSTRAK Penelitian ini dilatarbelakangi oleh masih dominannya pola pembelajaran sejarah yang berpusat pada guru dan bersifat satu arah, sehingga siswa cenderung pasif serta memiliki keterbatasan dalam mengembangkan kemampuan berpikir reflektif. Untuk mengatasi permasalahan tersebut, pendekatan Culturally Responsive Teaching (CRT) dipandang sebagai alternatif yang relevan karena menekankan keterkaitan materi ajar dengan latar belakang budaya dan pengalaman siswa. Penelitian ini bertujuan untuk menganalisis pengaruh penerapan CRT terhadap kemampuan berpikir reflektif siswa pada materi Peninggalan Sejarah Masa Islam di Indonesia. Desain penelitian yang digunakan adalah kuasi-eksperimen dengan model non-equivalent control group design. Subjek penelitian terdiri atas dua kelas, yakni kelas eksperimen yang memperoleh pembelajaran dengan pendekatan CRT dan kelas kontrol yang menggunakan pendekatan Teacher Centered Learning (TCL). Instrumen penelitian meliputi tes kemampuan berpikir reflektif dan angket respons siswa. Analisis data dilakukan melalui uji prasyarat, uji Independent Sample t-test, serta perhitungan Effect Size dengan rumus Cohen’s D. Hasil penelitian menunjukkan bahwa respons siswa terhadap penerapan CRT bersifat positif. Uji-t menghasilkan nilai signifikansi 0,000 < 0,05 yang mengindikasikan adanya perbedaan signifikan antara kelas eksperimen dan kelas kontrol. Nilai Effect Size sebesar 0,97 berada pada kategori sedang. Dengan demikian, penerapan pendekatan CRT terbukti memberikan pengaruh nyata terhadap peningkatan kemampuan berpikir reflektif siswa, di mana siswa lebih mampu memahami materi, melakukan evaluasi, serta membentuk pengalaman baru dalam merumuskan solusi berdasarkan pemahaman mereka sendiri.