Rear Admiral Sir Sydney Marow Eardley-Wilmot (3 October 1847 – 27 February 1929) was a Royal Navy officer who took an active part in the Suakin Expedition and who lost a hand as the result of an explosion at the torpedo school HMS Vernon. He had a specialism in naval gunnery and was Superintendent of Ordnance Stores at the Admiralty during the period of the Anglo-German naval arms race when the Dreadnought Fleet was developed. He advocated for the construction of the largest guns possible. He wrote a number of works of naval history as well as two novels that feature near-future naval warfare.