HMS Cornwall was a 9,000-ton Monmouth-class armoured cruiser of the Royal Navy. She was launched at Pembroke, Wales in 1902, and commissioned in 1904.

On the outbreak of World War I in 1914 she was despatched to West Africa to intercept German merchant shipping. She then proceeded to the Falkland Islands in the squadron commanded by Vice-Admiral Doveton Sturdee, consisting of the battlecruisers Inflexible and Invincible, the pre-Dreadnought battleship Canopus, two armoured cruisers, three light cruisers and one armed merchant cruiser.

On 8 December 1914 Sturdee's squadron encountered a German squadron commanded by Vice-Admiral Maximilian von Spee, consisting of the heavy cruisers Scharnhorst and Gneisenau together with the light cruisers Nürnberg, Leipzig and Dresden

In the ensuing battle of the Falkland Islands Cornwall assisted in the sinking of Leipzig. Of the five ships of the Kaiserliche Marine only Dresden escaped.

Following the battle Cornwall returned to West Africa. In June 1915 she was sent to support the Dardanelles Campaign.

In October 1916 she was sent to the East Indies and China Stations to protect Allied shipping from surface raiders. She returned to the United Kingdom in 1917 where she was refitted. For the remainder of the war she escorted convoys between Canada and the UK.

She paid off early in 1919 and was scrapped in 1920.

See HMS Cornwall for other ships of this name.