The Gunnery Division was a Directorate of the Admiralty Naval Staff of the Royal Navy responsible for the tactical use of naval weapons and the training of naval personnel in relation to operational requirements. It was established in 1920 when the Gunnery and Torpedo Division was separated into an independent Gunnery Division and Torpedo Division. It existed until 1964 when the Department of Admiralty was abolished and replaced by a new Ministry of Defence.

Prior to 1918 responsibility for naval ordnance and gunnery training lay with Naval Ordnance Department. In 1918 the Naval Artillery and Torpedoes Division was established; in June 1920 it was split up into the Gunnery Division and the Torpedo division. It was created as new directorate of the Admiralty Naval Staff in primarily to deal with questions of the tactical use of these weapons and the training of personnel and to facilitate the clear connection between the use of the weapon and operations. The training and the tactical aspects of weapons constitute a sphere common to the naval staff, the Admiralty technical departments and the fleet. Following on from the lessons learnt during World War I on 19 April 1920 the Gunnery and Torpedo Division was split up and according to author Norman Friedman responsibility for Gunnery initially concerned with fire control was specifically created for a new Director of the Gunnery Division, Naval Staff, Captain Frederic C. Dreyer who was Admiral Jellicoe's chief fleet gunnery officer. In 1928 the Gunnery Division was disbanded from the Naval Staff until the advent of World War II when in 1941 it was re-established as the Gunnery and Anti-Aircraft Division it remained a naval staff division until 1964.

Instructions issued for the Gunnery Division as part of the Naval Staff re-organisation as of 1921 and held by the National Archives (U.K.) included:

A) The Director of the Gunnery Division (D. of. G.D.) will advise on the following:

He is responsible for keeping the Naval Staff in touch with progress and general development of the Fleet in gunnery and chemical warfare and with the method of conducting gunnery and chemical warfare at sea.

B) He will advise on:

Note.—Technical advice on the design of gunnery material, chemical warfare material, and material for counter measures is the function of the D.N.O.

C) He is responsible for scrutinising all reports of gunnery practices submitted to the Admiralty for review by Senior Officers and Cs.-in-C., and will advise as to the action necessary:—