This study aims to analyze the communication network of mosque administrators in prospering mosques in Dairi Regency. This study uses a descriptive qualitative approach using a case study approach. This study uses documentary studies, interviews, and observations. This study revealed that the communication network of mosque administrators in Dairi Regency plays a central role in the process of mosque prosperity. The main findings that were successfully identified specifically include: Intensity of Mosque Administrator Communication, Mosque administrators in Dairi Regency, especially core administrators (chairman, secretary, treasurer), have a high intensity of communication through routine discussions after prayers and informal meetings. This communication strengthens internal cooperation and supports the process of building and managing mosques. Communication between mosques is still personal and not yet structurally organized. Content of Communication Messages, The content of the administrator's messages focuses on matters of construction, maintenance, finance, and evaluation of mosque activities. For the congregation, the messages are in the form of invitations to participate in worship and social activities. To the Government and KUA, the messages are administrative in nature. Discussions are also carried out through WhatsApp groups facilitated by the Ministry of Religion, although there is no official organizational forum between mosque administrators. Communication Media Used, The main communication media are WhatsApp and telephone because they are practical and easy to use by administrators, most of whom work as farmers. For formal purposes, such as meetings and activity invitations, printed media in the form of letters are used. This combination of media supports effective communication, although the limitations of communication structures between mosques remain a barrier to broader collaboration.