On September 21, 1797, Archbishop Varlaam Petrov of Tobolsk issued a decree to Protopriest Alexei Alekseev from Krasnoyarsk. The document stated that the parishioners of Kansk requested to replace the wooden Spasskaya Church with a stone one, with an altar dedicated to the Protection of the Holy Virgin. Stone and timber had already been prepared for construction. Work began on May 18, 1800, and was completed in October 1804. By this time, the stonework on the cold church was finished, and the warm altar was fully prepared, consecrated on January 22, 1805. The cold church was consecrated on June 5, 1814.

From 1834 to 1839, a warm altar dedicated to St. Nicholas the Wonderworker was built on the northern side, consecrated on January 18, 1839, along with a four-column portico at the western entrance, executed in the classical style. In 1911-1912, provincial architect V. Sokolovsky developed a reconstruction project, under which a new southern altar, similar to the northern one, was built, and an extension to the western facade was added with the portico relocated. The ceilings of the refectory were raised, and second-light windows were added. The lower tier acquired classical forms.

In 1937-1938, the cathedral was closed, the domes were removed, and the building was used for an aeroclub. In 1946, the cathedral was returned to the faithful, but in 1964 it was closed again and housed a theater, and later a local history museum.

By 1961, the upper tiers of the five-domed church and bell tower, as well as the domes of the altars and apses, were dismantled. The porticoes on the northern and southern facades were lost. An inharmonious extension was added to the eastern facade, covering the altar apses. Some openings were bricked up, and the rooms were re-planned.

In 1987, a diploma project for the graphic reconstruction of the cathedral was completed at Krasnoyarsk ISI under the guidance of K.Yu. Shumov, Yu.I. Grinberg, and A.G. Lavrov. The project was authored by E. Slizhevskaya. In 1992, the cathedral was returned to the faithful and partially restored. The bell tower and the square base of the main church with five domes were restored, and the main altar was consecrated in honor of the Holy Trinity.

The main volume of the church includes a high square temple part with a semicircular apse, a refectory, and a tiered bell tower. Late extensions include the northern and southern altars and the western extension. The main entrance is decorated with a four-column portico of the Tuscan order.

The high square base of the church is topped with a shaped dome and five domes. The bell tower is octagonal in the upper tiers, with a dome on an octagonal drum. The altar apse is also crowned with a dome on an octagonal drum. The square space of the main church connects to the refectory through arched openings. In the western part, there is a church narthex with a staircase to the bell tower. The western extension contains three rooms.

On the church's square base, there are second-light windows with semicircular finishes, while in the refectory, there are round second-light window openings. The square base is topped with a half-dome, with a round window on the central axis. On the sides rise two-tiered octagonal drums of the domes. The drum of the small octagon is pierced with narrow openings. The southern altar is topped with a shaped dome on an octagonal drum.

The window openings are framed with profiled moldings and rest on window sills. The round window opening of the square base is framed with finely profiled moldings. The cornice of the first tier has a flat frieze. The corners of the bell tower are treated with pilasters, and the openings of the ringing tier have archivolts. The bell tower is decorated with cornices with brackets. The second-light windows are framed with moldings. The corners of the square base are treated with pilasters with panels. The walls of the refectory and apses are crowned with cornices.

The interior develops along the longitudinal axis of the building, including the western extension, narthex, refectory, and the church itself with the apse. The interior of the church develops in height, with an active role of the vaulted ceiling of the refectory and the second-light windows.

The cathedral, a monument of 19th-century architecture, is the oldest stone building in Kansk and an example of the Yenisei school of late Siberian Baroque. The main volume includes a high square base with five domes. The northern and southern altars adjoin it, and to the west, the refectory and bell tower. The cathedral is located in the central square of the historical center of Kansk and is an important urban planning dominant.