Tønsberg Cathedral is a cathedral that is the episcopal seat of the Diocese of Tunsberg within the Church of Norway. It is located in the centre of the city of Tønsberg in Tønsberg Municipality in Vestfold county, Norway. It is the main church for the "Tønsberg domkirke" parish which is part of the Tønsberg domprosti (deanery) in the Diocese of Tunsberg. The brown brick church was built in a long church design in 18 using plans drawn up by the architect. The church seats about 500 people.

Tunsberg is a diocese of the Church of Norway. It includes all of the parishes located within the counties of Vestfold and Buskerud, with the cathedral located in the city of Tønsberg. The Diocese of Tunsberg consists of the cathedral deanery and eight rural deaneries.