During the major reconstruction of the Cathedral (1783–1801), Laurynas Gucevičius designed the elliptical Chapel of St Ladislaus. Fragments of frescoes with the Latin inscriptions ZELUS (zeal) and FIDES (faith) have survived, and the altar, installed in the mid-19th century, features a plaster statue of St Ladislaus (1861–1863) by Henrik Dmochowski. In 2021, the restored dome decoration with illusionistic painting was revealed.

St Ladislaus is the patron saint of Hungary and of Vilnius Cathedral, associated with legends of miracles, military victories, and healing. Together with St Bishop Stanislaus, he is regarded as a patron of the Cathedral. During the Christmas season, a Nativity scene is displayed in the chapel.