Arundel is a market town and civil parish in a steep vale of the South Downs, West Sussex, England.
The much-conserved town has a medieval castle and Roman Catholic cathedral. Although smaller in population than most other parishes, Arundel has a museum and comes second behind much larger Chichester in its number of listed buildings in West Sussex. The River Arun runs through the eastern side of the town.
Arundel was one of the boroughs reformed by the Municipal Reform Act 1835. From 1836 to 1889 the town had its own Borough police force with a strength of three. In 1974 it became part of the Arun district, and is now a civil parish with a town council.