Kościół pw. Wszystkich Świętych

All Saints' Church in Mielżyn is a Roman Catholic parish church located in the village of Mielżyn, in Wielkopolskie Voivodeship, at Kościelna Street.

The church was built at the end of the 16th century in the Gothic style with Romanesque features. It was consecrated on July 19, 1592 by Bishop Jan Gniazdowski, suffragan of Gniezno. Until 1781 the building had the so called "oblong form", but at the end of the eighteenth century it was renovated and St. Anne's chapel was added to the body of the church from the north, and then St. Cross chapel. In the middle of the 19th century the church was completely renovated and the present organ was built. In 1985 the church was extended and given a cruciform shape.

The main altar was made in the 18th century, and it houses a painting of All Saints from the same period.

The church also has two side altars.

The most important monuments of the temple are: a Gothic door to the sacristy from the second half of the 16th century, a stone stoup from the same time and a wooden crucifix from the 18th century.