The one-story building of the Synod, located on the northwest side of the Mother Cathedral, was built in 1896-1897, during the reign of the Patriarch Mkrtich I Khrimyan, where the Patriarchal Chancellery and the office of the Synod functioned.
From 1920 to 1921, the building was confiscated by the Soviet authorities of Armenia, and in later years it was again returned to the Mother See. Until 2011 it served as the administrative building of the Mother See.
In 2011, it was decided to transform the building. For this purpose, the existing building was expanded 19 m to the north and was supplemented with 8 offices located on both sides of the corridor forming the continuation of the previous part (author of the project: A. Sahakyan).