The first Spaso-Transfiguration church of the monastery, built in the 14th century, was likely wooden. After the fire in 1507 that destroyed most of the monastery buildings, a new stone Spaso-Transfiguration cathedral was erected, which has survived to this day and is the oldest stone structure of the Spaso-Evfimiev Monastery. It was built over the grave of its founder, Abbot Evfimy. Initially, the cathedral was small, and when the new building was constructed in 1594, it was incorporated into the new church as the Evfimiev chapel. The interior walls of this chapel are painted with scenes from the life of Saint Evfimy, including the selection of the site and the beginning of the monastery's construction. These paintings were discovered during restoration work in the 1970s and were partially uncovered under the guidance of restorer A. P. Nekrasov. The cathedral itself has four pillars and five large drums, through the windows of which light penetrates onto the walls, painted with frescoes in 1689 by a group of renowned Kostroma icon painters, Guriy Nikitin and Sila Savin. For a long time, the cathedral remained without internal paintings, and its snow-white walls were adorned with numerous icons in rich frames and silk embroidered veils, which gave the interior a special beauty and uniqueness.

The cathedral was executed in the traditions of white stone architecture of Suzdal from the 12th-13th centuries and initially resembled the Nativity Cathedral of the Suzdal Kremlin. However, as a result of numerous reconstructions, its appearance changed. Originally, the church had three porches, like the Nativity Cathedral of the 13th century, but in the 18th century, they were combined with a gallery. In 1865, a new chapel in honor of St. Sergius of Radonezh was added to the northern facade on the eastern side for symmetry.

In 2012-2013, current repairs were carried out on the gallery of the Spaso-Transfiguration Cathedral. Restoration work on the paintings inside the cathedral was conducted in 2013-2014 and 2017-2018.