The church was founded by King Vakhtang Gorgasali at the time of the foundation of Tbilisi. According to the historians, during the second part of the 6th century Kartlian Lords started the building of Episcopacy Cathedral, cruciformed-domed church. The cathedral had been destroyed by enemies for several times, but it was restored, which can be proved by the inscriptions made on the walls.

We learn from the historic sources that Tbilisi Bishop Elise Saginashvili had built Sioni Dome for the second time in 1657. He had the entrance of the cathedral painted and decorated. The second inscription made in 1710 belongs to the period of King Vakhtang VI and it also tells about the renewal of the cathedral.

At the beginning of the 80s in the 20th century with the blessing of His Holiness Ilia II , a small chapel of St.King Vakhtang Gorgasali was built at the north entrance of the cathedral. It was painted during 2007-2009 years under the leadership of Lasha Kintsurashvili. In this process the following icon-writers also took part; Irakli Medoshvili, Temur Demetrashvili, Levan Davitiani, Irakli Parjanadze.