175th Heavy Anti-Aircraft Regiment, Royal Artillery (175th HAA Rgt) was an air defence unit of the British Army formed during World War II.

In April 1943 the regiment left AA Command and came under War Office control, preparatory to proceeding overseas.

[1][7][8][9][10] The vital naval base and airfield on Gibraltar had been overflown and sometimes attacked by Vichy French, Italian and German aircraft during 1940–42, and the AA defences had reached peak strength in early 1943.

On 7 March RHQ of 175th HAA Rgt took over operational control of 451 LAA Bty from 141st Light AA Rgt which was being withdrawn, together with 1 RDF Bty (radar), 1 AA 'Z' Troop (Z Battery rocket launchers) and 142 Gun Operations Room.

Finally, on 26 October, 441 HAA and 451 LAA Btys were disbanded as the men were sent back to the UK, and 1 Radar Bty became independent; there were no other changes to the end of the war.