The purpose of the study to examine the factors causing the constrained activities of da'wah in the holy month of Ramadan in the Darussalam Mosque Kampung Pisang Sorong City west Papua. The da'wah activity in question is a routine lecture by the dai (preachers) conducted every night of ramadan that has been programmed by the Ministry of Religious Affairs of Sorong City. This research uses qualitative research type. As for data collection, researchers use interview methods to primary informants, namely the management of The Darussalam Mosque Kampung Pisang, the dai / mubaligh listed in the schedule of lectures, worshipers (mad'u) Darussalam Mosque Kampung Pisang, and the Ministry of Religious Affairs that compiled the schedule of the lecture. As for the observation method, the author directly observes the situation in the field both from BKM / the manager of The Darussalam Mosque Kampung Pisang, Jamaah (mad'u) Masjid Darussalam Kampung Pisang, the dais listed in the lecture schedule, and the Ministry of Religion. This research is expected to be a reference in overcoming the vacancy according to the causative factors in the holy month of Ramadan throughout the Mosque, especially in the Darussalam Mosque Kampung Pisang. Thus da'wah activities can run well without any obstacles.