Penelitian ini merupakan penelitian kualitatif dengan pendekatan deskriptif, bertujuan untuk mengidentifikasi kemampuan komunikasi matematis berdasarkan disposisi matematis pada materi persamaan garis lurus. Subjek penelitian ini ialah siswa kelas VIII yang mewakili setiap kategori disposisi matematis yaitu tinggi, sedang, dan rendah. Teknik pengumpulan data dilakukan dengan pemberian angket, tes, dan wawancara. Hasil penelitian menunjukkan bahwa seluruh siswa pada setiap kategori disposisi mampu menuliskan solusi secara sistematis dan mampu menggunakan simbol matematika dengan tepat. Namun, siswa DMR kurang mampu memahami masalah sehingga terdapat kekeliruan penyelesaian. Perbedaan kemampuan siswa terlihat dari kemampuan menggambarkan grafik. Siswa DMT menggambarkan grafik dengan tepat. Sedangkan, siswa DMS menggambarkan grafik yang kurang tepat. Adapun, siswa DMR tidak mampu menggambarkan grafik solusi dari soal.Kata Kunci: Kemampuan, Komunikasi Matematis, Disposisi Matematis, Persaman Garis LurusThis research is qualitative research with a descriptive approach, aiming to identify mathematical communication skills based on mathematical disposition in straight-line equation matter. The subject of this research are students of class VIII who represent each category of mathematical disposition that is high, medium, and low. Data collection techniques are done by giving questioner, tests, and interviews. The results showed that all students in each disposition category were able to write solutions systematically and were able to use mathematical symbols appropriately. However, DMR students are less able to understand the problem so there is a mistake in solving it. The difference in students' abilities can be seen from the ability to graph. DMT students draw graphs precisely. Meanwhile, DMS students draw inappropriate graphs. As for the subject, DMR students are not able to draw a solution graph of the problem.Keywords: Ability, Mathematical Communication, Mathematical Disposition, Straight Line Equation