The squadron formed at Gosport on 1 February, 1915 and after completing its training, embarked for the Middle East in November.

Later, the squadron formed a crucial component of the fighter defence of England until the advent of Second World War, although during the Abyssinian crisis of 1935, the unit lost most of its Bristol Bulldogs as reinforcements for other squadrons moving to Africa, forcing it to fly older Hawker Harts for a period. In June 1939, Hurricanes arrived and with these, the unit began defensive patrols until the German attack on France in May 1940.

Fighter sweeps began over Holland, Belgium and France and soon enough, the squadron began to encounter the Luftwaffe. Its very first combat, over Holland, three Me109s and two Henschel Hs126 were shot down. However, the squadron also lost five of its own, including the commander Squadron leader G.C. Tomlinson who was killed. Later using airfields in rapidly-faltering France, the squadron attempted to cover the retreat of allied troops westwards. By June the squadron had moved to Brittany as the remnants of BEF (British Expeditionary Force) and the RAF in France withdrew, eventually retiring to the Channel Islands two days before returning to England. 

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With France gone, the squadron began to operate with No 11 Group over southern England. Rebuilt and reinforced, the squadron was heavily engaged during the Battle of Britain, claiming the destruction of 67½ enemy aircraft. Still in action by November, after the battle had been officially concluded, the squadron had its heaviest day on the 8th, when they encountered 25 to 30 Ju87 Stuka dive-bombers escorted by Me109 attacking two British destroyers in the Channel. Sweeping in, the squadron began a prolonged dogfight after which they claimed 13 Stukas destroyed, with another seven planes probably destroyed and one damaged.

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Retired to northern Scotland in April 1941, the squadron received orders to transfer to India in November – even before the advent of Japanese opening blows. Sent to the Far East with the intention of reinforcing British forces in Malaya, the squadron diverted to Burma as most of Malaya had already fallen in Japanese hands by December. Once in Burma, it was handed the difficult assignment of stemming the Japanese tide against Rangoon. Stationed at Mingaladon, outside Rangoon by January 1942, the squadron’s score began to soar again as numerous Japanese Ki-27 Nates fell to their guns, but these came at the cost of grievous losses of own. Finally, by March, cut-off and badly bruised at Lashio, No 17 withdrew to India and made it to Calcutta, where it regrouped.

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It now took on the air defense of India, with the remnants of other RAF fighter squadrons and the Royal Indian Air Force. In December 1942 when the Japanese attempted night raids against Calcutta, the squadron shot down its first Japanese plane over Indian soil on the night of the 23rd. More air defense sorties continued for the rest of the month and into January 1943, but from February, No 17 began ground attack sorties. Moving to Ceylon in August, they received Spitfire Mk VIIIs in March 1944 to replace their aging fleet of Hurricanes. Returning to the Burmese front in November, the unit participated in the allied recapture of the country, escorting supply-carrying Dakotas and averaging several ‘Cab-Rank’ missions over the battlefield. As an Allied victory in Burma appeared on the horizon, the squadron withdrew to India in June 1945 to prepare for the invasion of Malaya.

When the war ended before the planned invasion, No 17 simply moved to Malay onboard the Royal Navy carrier HMS Trumpeter on September 1, arriving at the landings beaches at Penang on the 9th. It later joined the Commonwealth Air Forces of Occupation in Japan in April 1946, disbanding there on 23 February 1948, its victory tally for World War II standing at 111 enemy planes destroyed with another 51 probably destroyed and 32 damaged.