Teacher is as the center of national education development, so it needs to have development for teachers to increase the professionalism and one of them is through teacher working group (MGMP). The objective of the research was to find out the professional competence of ISMUBA (Islam, Muhammadiyah, and Arab Language) teachers, the activities of MGMP ISMUBA in Bantul Regency, the attempts of professional competence development of ISMUBA teachers through MGMP. The research was descriptive qualitative in nature with data collection through documentation, observation, and interview. The results of the research obtained were: 1) The professional competence of ISMUBA teachers was categorized as good. 2) The process of the activity implementation still had obstacle, i.e. the lack of ISMUBA teacher commitment in attending the activity. 3) The attempts of professional competence development of ISMUBA teachers through training of learning method, workshop of learning media preparation held by MGMP.