ABSTRAK Penelitian ini bertujuan untuk menganalisis pengaruh penggunaan metode pembelajaran Problem Based Learning (PBL) terhadap peningkatan kemampuan penalaran siswa kelas 6 di SD Negeri Larangan 01 pada materi pembelajaran Bahasa Indonesia. Jenis penelitian yang digunakan adalah Penelitian Tindakan Kelas (PTK). Penelitian ini dilaksanakan pada semester genap tahun ajaran 2022/2023. Subjek penelitian ini adalah 26 siswa kelas 6 SD Negeri Larangan 01. Fokus penelitian mencakup keaktifan belajar dan kemampuan penalaran siswa dengan menggunakan tes tulis sebagai instrumen penelitian. Teknik pengumpulan data menggunakan observasi dan tes tulis. Data dianalisis secara desktiptif dan disajikan dalam bentuk tabel. Hasil penelitian menunjukkan peningkatan signifikan pada keaktifan belajar dan kemampuan penalaran siswa. Pada siklus I, tercatat peningkatan sebesar 75,15%, yang kemudian meningkat menjadi 83,5% pada siklus II. Hasil ini mencerminkan peningkatan sebesar 8,35% secara keseluruhan. Dengan demikian, dapat disimpulkan bahwa penerapan model pembelajaran Problem Based Learning dalam mata pelajaran Bahasa Indonesia dapat efektif meningkatkan keaktifan belajar dan kemampuan penalaran siswa. Kata kunci: problem based learning, bahasa Indonesia, kemampuan penalaran. ANALYSIS OF THE USE OF PROBLEM-BASED LEARNING METHODS IN IMPROVING THE REASONING ABILITY OF STUDENTS IN CLASS VI OF BAN 01 STATE ELEMENTARY SCHOOL IN INDONESIAN LANGUAGE LEARNING ABSTRACT This study aims to analyze the effect of using the Problem Based Learning (PBL) learning method on improving the reasoning ability of 6th grade students at SD Negeri Larangan 01 on Indonesian language learning materials. The type of research used is Classroom Action Research (PTK). This research was conducted in the even semester of the 2022/2023 school year. The subjects of this research were 26 6th grade students of SD Negeri Larangan 01. The focus of the research included learning activeness and students' reasoning skills using written tests as research instruments. Data collection techniques used observation and written tests. The data were analyzed descriptively and presented in tabular form. The results showed a significant increase in students' learning activeness and reasoning ability. In cycle I, an increase of 75.15% was recorded, which then increased to 83.5% in cycle II. These results reflect an increase of 8.35% overall. Thus, it can be concluded that the application of Problem Based Learning model in Indonesian subject can effectively improve students' learning activeness and reasoning ability. Keywords: : problem based learning, Indonesian language, reasoning ability.