The Church of the Most Holy Heart of Jesus in Żary is a well-preserved Gothic temple, built at the turn of the 13th and 14th centuries. The façade is decorated with ostroof windows and portals, as well as Gothic-style stairs. In the interior there are two tombs of the mighty von Promnitz family in Żary in the 16th and 18th centuries.
Construction of the temple was probably started in 1207, hence the first construction was Romanesque. This is reflected in the architectural elements preserved in one of the church's rooms. Repeated fires destroying the building made it rebuilt from gothic style and it has survived until the present. Also systematically, for over 300 years it was expanded, thanks to which it reached its present size. The church was severely destroyed during World War II. It was rebuilt in 1975-1984, complementing the elements made by local artists from Lower Silesia.
The parish church in Żary served the Catholic parishes until the sixteenth century. In 1524, during the wave of the Reformation, it was taken over by Protestants and served until the Second World War. Since its rebuilding, it belongs to the Zary diocese of Zielonogórsko-Gorzow.