This is a harmonious laconic and strict building. Its only decor consists of floral ornament on the door and window frames. The interior of the temple is divided into three parts by two rows of columns. The columns support the octahedral drum decorating the temple arch. The hallows of St. Gayane rest in the southern wall of the temple next to the altar niche. The 17 th - century wall frescos depicting the Nativity have survived above the western entrance.
In 1652 the temple was capitally renovated and in 1683 they added the gallery for Armenian Church ministers' burial. From the sides the gallery is decorated with graceful belfries.
There is a special room in St. Gayane Temple for sacrificial animals slaughter. The ceremony of sacrifice has been practiced by Armenian Church since the time of St. Gregory the Illuminator and is called matakh. It is observed for various occasions: weddings, births and so forth.