The temple, erected from brick and stone blocks between 1490 and 1510, is a distinctive cityscape feature today. It is a late Gothic, three-nave hall church with rows of chapels along the side aisles, a lower and narrower presbytery, vestry, and treasury covered by a gabled roof with a cupola turret. Both wealthy families (the Kromer family, the Sułowski family, the Ligęz family, the Wielkopolski family) and craft guilds (weavers, carpenters, shoemakers, bakers) have their chapels in the Biecz church. The oldest part is the presbytery, dating from around 1480, whose construction began in 1326.

Inside the collegiate church, the rainbow beam contains a scene of the crucifixion of Christ from the 15th century. Late Renaissance, richly carved stalls from the 17th century are on the sides of the presbytery. The Mannerist main altarpiece of 1604 shows a painting made in the 16th century depicting the Deposition from the Cross, one of only three such paintings in the world. It is most likely from the Italian painting circle and attributed to Michelangelo's workshop. There is also a late Gothic bronze baptismal font from the 15th century and twelve side altars in various styles. The Oratory of Saint Hedwig, where, according to legend, the Queen prayed, has housed a reliquary with her relics since 2006. The paintings in the presbytery, mainly on the vault, were done by Włodzimierz Tetmajer. The vaults are stellar in the chapels, with a rare 'eye' motif attracting attention in one of them.

Next to the church is a bell tower from the 15th century, which served as a defensive tower - it was called the butchers' tower because the butchers' guild were assigned to man the tower when the city was under attack. The bell tower joins the neo-Gothic Chapel of St Barbara and the old vicarage, one wall of which is part of the town's former defensive wall.