The original building of this mosque can be traced back to 1967  when the Ammar Mosque was just a small mosque built adjacent to the Muslim cemetery in Hong Kong  and was used primarily to offer funeral prayer. With the increase in Muslim population on Hong Kong Island, Muslims living close by began to use the Mosque for daily prayers as well. A new and larger Mosque was constructed after World War II which remained in use until December 1978 when it was resumed by Government to construct approach roads for the Aberdeen Tunnel. The current building was established in 1981 and in 2012, the mosque underwent major renovation which included the installation of new central air conditioning system, CCTV, new outer painting colour, replacement of toilet and ablution areas, new study rooms etc.

Ammar Mosque was the brainchild of a Chinese Muslim architect. This holy place allows only its devotees.  The mosque was designed by a Chinese Muslim, Ramju Sadick. The centre of the mosque is an eight-storey complex with multi-purpose facilities, such as ablution halls for men and women on the first floor, mosque male prayer hall on the second floor, mosque female prayer hall on the third floor and Chinese restaurant, Halal bakery, medical services, classrooms, library, offices for Imam and Quran teachers, conference and seminar rooms on the fourth until eighth floor.