Musthafawiyah Purba Baru Boarding School is one of the oldest and most famous Boarding school in Sumatra. In addition its many characteristics and advantages, this boarding school faces several problems in Arabic teaching. This research aims to find out the problems faced by Musthafawiyah Puba Baru boarding school in Arabic teaching and some solutions to solve the problems. This research uses a descriptive qualitative approach. The method of collecting data in this research is observation, interview, and documentation. The sources of data in this research are teachers and students in the third year at this school and its principle. The results of this research are: Among the problems of Arabic teaching at Musthafawiyah Purba Baru are: a lack of students’ understanding of the teaching materials presented by the teacher, a low of students’ motivation in teaching, a decrease in the adequacy of skills in teaching and learning for some Arabic teachers, and a decrease in educational facilities and infrastructure according to their function. The solutions to solve these problems, are: increase the students’ awareness of the importance of studying the Arabic and increase the teacher’s awareness of his responsibility in teaching, and the teacher must give positive encouragement to his students, and giving the special training to teachers about efficiency in the teaching and learning process and suggest them to continue their study until the university, and completing the activation of all facilities in this boarding school according to its function to complete the effectiveness of teaching and learning.