The greatest sacral monument in Żnin is the Gothic parish church. It was built in the 15th century, but it is known that there was previously a sanctuary in this place. There are some blocks of stone in the walls that were left after the previous Roman building. The present design of the monument is the result of the renovation by the Bishop Stefan Łubieński. Only the Gothic peripheral walls of the medieval building remain. The tower was added in 1910–24.

In the Baroque interior of the church, many moveable monuments of the art of Żnin are preserved. Among them we can find a Late Gothic Pieta from the 16th century and – on the rood beam – the Group of Crucifixion from the same period. The Baroque and the Late-Classicistic altars were created at the end of the 18th century. The main altar, partly made of stucco, is decorated with the figures of adoring angels. After the Dominican monastery in Żnin was shut down, many objects, the liturgical vestments, and the 17th-century picture of the Mother of God with the Child were moved to the church. This is the miraculous picture of Our Lady of Consolation, which is located in the right nave. It is known that it was previously worshipped in the Dominican monastery.