The permanent collection of the Palazzo Doebbing museum is divided into thematic areas. One is dedicated to ancient art and houses artifacts from the Roman era, among which the Ephesus from the 1st century AD is particularly relevant, as a testimony to the millenary identity of Sutri. There is also a section dedicated to sacred art that preserves and enhances a precious selection of works from the Cathedral's treasure.

Lastly, the art gallery displays paintings and panels from different buildings of the Diocese of Civita Castellana, among which stand out masterpieces by artists such as Antoniazzo Romano, Sano di Pietro, and Antonio da Viterbo. The museum hosts numerous exhibitions throughout the year, always included in the entrance ticket without additional charges.