The Gniezno Doors are a pair of bronze doors placed at the entrance to Gniezno Cathedral in Gniezno, Poland. They are decorated with eighteen bas-relief scenes from the life of St. Adalbert, whose remains had been purchased for their weight in gold and brought back to, and enshrined in, the cathedral. The cathedral is a Gothic building which the doors predate, having been carried over from an earlier temple. The doors were made around 1175, in the reign of Mieszko III the Old, and are one of the most important works of Romanesque art in Poland.

Gniezno is a city in central-western Poland, about 50 kilometres east of Poznań. Its population in 2021 was 66,769, making it the sixth-largest city in the Greater Poland Voivodeship. One of the Piast dynasty's chief cities, it was the first historical capital of Poland in the 10th century and early 11th century, and it was mentioned in 10th-century sources, possibly including the Dagome Iudex, as the capital of Piast Poland.