Pada kegiatan pembelajaran siswa kelas VI di SD CTR, ditemukan beberapa sikap tidak disiplin pada diri siswa yang berdampak pada efektivitas belajar siswa. Tujuan dari penelitian ini yaitu untuk mengetahui penerapan peraturan kelas dapat meningkatkan kedisiplinan dan cara penerapan peraturan kelas dalam meningkatkan kedisiplinan siswa kelas VI SD CTR. Penelitian ini menggunakan Metode Penelitian Kelas (PTK) dengan model “Kemmis dan Mc Taggart” yang dilakukan dalam tiga siklus dan dilaksankan pada tanggal 20 Oktober 2015 sampai 28 Oktober 2015. Subjek dalam penelitian ini adalah siswa kelas VI SD CTR yang berjumlah 21 siswa. Instrumen yang digunakan adalah lembar checklist penerapan peraturan kelas, lembar observasi mentor, angket siswa, dan refleksi peneliti. Data yang didapat kemudian dianalisis secara deskriptif naratif dengan pendekatan kualitatif. Hasil penelitian menunjukkan bahwa penerapan peraturan kelas dapat meningkatkan kedisiplinan siswa kelas VI SD CTR hingga mencapai 100%, yang ditunjukkan dengan: siswa dapat mengikuti dan melaksanakan instruksi guru dengan cepat, siswa fokus pada kegiatan belajar, dan pelajaran berlangsung dengan kondusif. Dengan demikian, dapat disimpulkan bahwa penerapan peraturan kelas dapat meningkatkan kedisiplinan siswa kelas VI SD./ In the 6th grade of CTR Elementary School learning activity, researcher found some students indiscipline behavior that made the learning ineffective. The purpose of this research were to know the implementation of classroom rules could increase the discipline and the way to implementing the classroom rules that could increase the discipline of 6th grade students in CTR Elementary school. The method used in this research was Classroom Action Research (CAR) by using Kemmis and Mc Taggart’s model, that done in three cycles and have been held on October 20th 2015 until October 28th 2015. The subject of this research were 6th grade students in CTR Elementary School who consisted 21 students. The instrument that used in this research were classroom rules implementation checklist sheet, mentor’s observation sheet, mentor’s interview sheet, student’s interview sheet, student’s questioner, and researcher’s personal reflection. The data result was analyzed by narrative description method with qualitative approach. The result of this research proved that the implementation of classroom rules could increase the discipline of 6th grade student in CTR Elementary School for 100%, which showed by: students obeyed teacher’s instruction quickly, students focused on learning activity, and the leaning went conducive. In conclusion, the implementation of classroom rules could increase the discipline of 6th grade student of CTR Elementary School.