The church interior is mainly Gothic: the cycle of panel paintings on the main altar dates back to 1450 – 1460, the side altar of Apostles to 1470 – 1480, the side altar of St. Catherine to 1493. The relief of the Virgin Mary´s coronation on a side altar was made after 1500. The baptistery comes from 1472. In 1469, Master Simon made the stallum (the pew for very important persons) and in 1518, Hans Tischler made the pew for senators. The main spectacle of the present-day main altar is the Christ on the cross. It used to stand on a cross beam in the centre of the church. It was placed onto the main altar only in 1868. It is probably the most valuable part of the church. There is an assumption that it is the work of the Cracowian Master Vít Štos dating back to the end of the 15th century. However, we do not exclude that the altar also migt be an early work of the Master Paul. A research will give a definite answer.
Two galleries and two organs are very unique. The smaller organ from 1651, which is the work of Bartolomej Fromm, was repaired and one can play it even today. It belongs to the most valuable organs of its kind in Slovakia. There are many stone gravestones from the 16 - 18. century in the church. The oldest one, dating back to 1520, belongs to the Castle Captain Krištof Varkoč. Leftwards from the altar, there is the tomb of the Thököly family which comes from the times when the church belonged to Protestants (1531 – 1673, 1678 – 1687 and 1705 – 1709). In the half of the 18th century, the great Baroque modification of the church was carried out. The church had been repaired many times during the 19th and 20th century. In 1998, it was raised to the status of Basilica Minor. Thus, it became the first basilica in Slovakia which was not Marian.