The cathedral dedicated to Saint and Righteous Procopius, Ustyug Miracle Worker, holds the second place in significance within the cathedral complex after the Assumption Cathedral. Since 1683, it has served as the cathedral, and Procopius himself was buried on the riverbank near the Assumption Cathedral. Blessed Procopius of Ustyug was canonized on February 26, 1547, died in 1303, and his memory is celebrated on July 8. In 1458, a modest wooden chapel was built over his grave, which was replaced in 1471 by the first wooden church. The church was consecrated in honor of Boris and Gleb, the patrons of the Russian military, as Procopius had not yet been canonized.

The church has five domes, with a bell tower at the southwest corner housing 10 bells, the largest of which weighs 120 poods. In 1695, by the order of Ustyug Bishop Alexander, the bell tower was dismantled, and the materials were used for the construction of the archbishop's courtyard. In 1720 and 1724, the vaults of the Procopius Cathedral were raised, and the supporting columns were removed. In 1902, an altar in honor of Tikhon of Zadonsk, a sacristy, and a refectory were added. The church still houses the tomb with the relics of Saint Procopius, established in 1833, the only one preserved after 1917. At the foundation of the church lies a black stone, which, according to legend, fell from a stone cloud and on which Procopius loved to sit and reflect. This stone crowns his grave.

Among the attractions of the Procopius Cathedral is a five-tiered iconostasis with icons from the 17th and 18th centuries, likely created after the reconstruction of 1720-1724. In the local row of the iconostasis, several icons from the 16th and 17th centuries have been preserved, the oldest of which is "Procopius the Righteous in Life." Of interest is a stone cross depicting the crucifixion and God Sabaoth, inserted into a 17th-century icon. On March 21, 1940, the cathedral was closed, and in 1946 it was returned to the faithful. In 1964, the cathedral was closed again and handed over to the local history museum, where a branch of the museum and a planetarium were established. The reliquary with the relics of Saint Procopius was transferred to the Church of Stephen of Perm. After 30 years, in 1994, the parishioners were returned the Tikhon Chapel of the Procopius Cathedral, and on October 31, 1995, the entire Procopius Cathedral. The reliquary with the relics of Procopius the Righteous returned to its original place.