HMS Arethusa was the name ship of her class of light cruisers built for the Royal Navy. She was built by Chatham Dockyard, with the keel being laid down on 25 January 1933. She was launched on 6 March 1934, and commissioned 21 May 1935 by Captain Philip Vian.

The Arethusa class was a class of four light cruisers built for the Royal Navy between 1933 and 1937 and that served in World War II. It had been intended to construct six ships, but the last pair, Polyphemus and Minotaur, were ordered in 1934 as the 9,100-ton Town-class Southampton and Newcastle.