54th (City of London) Heavy Anti-Aircraft Regiment was a volunteer air defence unit of Britain's Territorial Army from 1922 until 1954.

When the Territorial Army (TA) was reformed in 1922 it included a number of dedicated AA units of the Royal Garrison Artillery (RGA).

[6] 54th AA Regiment formed an additional battery, No 312, at Putney on 1 April 1939, as part of the expandion of the TA following the Munich Crisis.

162 (City of London) Battery went to East Africa Command, where it later formed part of a composite 'F' Regiment.

[19][20][21][22] In May 1943, 54 HAA Regiment moved to Egypt, where it came under the non-operational 8th AA Bde in Middle East Forces.

312 Battery moved up and came under 89th HAA Rgt/AA Defence Command at Benghazi[23] but the rest of the regiment remained in Egypt until it was placed in suspended animation on 27 February 1945.