The PZL P.24 was developed as an export version of the PZL P.11, a gull-wing all-metal fighter designed by Zygmunt Puławski. The P.11 was powered with a license-built Bristol Mercury engine. The license did not permit export sales, so the French Gnome-Rhône company proposed using their engines in the P.11. The airframe of the P.Z.L. P.11 being redesigned to accept a new Gnome-Rhone engine designated 14Kds Mistral Major and rated at 760 hp / 567kW. The first P.24/I prototype, based on the P.11a, was flown in May 1933. The initial flight of the P.Z.L. P.24/I prototype ended in a forced landing when the propeller disintegrated. The P.24/I did not fly again until October 1933, showing a need for many modifications which were introduced in the P.24/II second prototype. The second P.24/II prototype, named the "Super P.24", set a world speed record for radial engine-powered fighters (414 km/h) on 28 June 1934. The third P.24/III prototype was the "Super P.24bis" with a more powerful 694kW 14Kfs engine, flown in 1934 and armed with two 20mm cannon and two machine-guns. The armament was a combination of 20 mm Oerlikon FF cannon and 7.92 mm Colt-Browning machine guns in the wings. The type was shown at the Paris air show in 1934 attracting great interest from the participants.
The aircraft was conventional in layout, with high wings. It was all-metal and metal-covered. The wings had a gull-wing shape, with a thin profile close to the fuselage, to provide a good view for the pilot. This configuration was developed by Zygmunt Pulawski and called "the Polish wing". The canopy was closed (apart from prototypes). An internal 360 liter fuel tank in the fuselage could be dropped in case of fire emergency. It had conventional fixed landing gear, with a rear skid.
The first export order came from Turkey, which not only negotiated a licence for the manufacture of the P.24, but also ordered 14 P.24A fighters generally similar to that shown at Paris, 26 P.24C aircraft with four wing-mounted machine-guns, and components plus raw materials for the assembly of 20 more P.24As. The 20 P.24A/Cs were built under license in Turkey in Kayseri, followed by an additional 30 P.24G aircraft. Turkish P.24s were used for training until the late 1940s. Some were refitted with Pratt & Whitney Twin Wasp engines.
Next came an order from Bulgaria for 14 P.24B aircraft which were similar to the P.24C apart from installed equipment and were delivered from early 1938, followed by 24 P.24Cs and 26 examples of the P.24F, the final development of the type, which introduced a 723kW Gnome-Rhone 14N.07 engine of smaller diameter and had twin cannon and twin machine-gun armament. 22 were delivered from Poland in July 1939, just before the outbreak of World War II. The remaining four, lacking propellers, were bombed in the Okecie factory in September 1939 by the Germans.
The P.24E, developed to meet a Romanian requirement, was generally similar to the P.24C: six built by P.Z.L. had 671kW Romanian-built Gnome-Rhone 14Kllc32 engines, but later examples of the 40 or so P.24Es built by I.A.R. in Romania between 1937 and 1939 had the 701kW I.A.R.-built 14KMc36 engine.
In late 1939 I.A.R. developed a low-wing version of the P.24E under the designation I.A.R.80. Some components of the P.24E, mainly its tail section, were used in construction of the IAR 80. The four machine-gun equivalent of the P.24F had the designation P.24G.
The Greek Air Force first bought five P.24As in 1937, then 25 P.24Fs and six P.24Gs in 1938. The contract of the P.24 supply was signed in September, 1936, with final delivery date in May 1937 (due to the delayed delivery of the "Skoda" LK 32 machine guns from the Czechoslovakian construction factory). They had the standard equipment specifications with German radio and American oxygen supply system. They comprised almost the entire fighter strength of this last air force and were deployed with considerable success against both the Luftwaffe and Regia Aeronautica. The fighters were used to guard Bucharest and the Ploieşti oilfields from Soviet bombers at the start of Operation Barbarossa. Flying from Otopeni military airbase, the PZL P.24 fighters managed to shoot down 37 unescorted VVS bombers. 11 were destroyed on the ground. The P.24E was also used for ground attack missions until the end of 1941 and after 1942 it was relegated to training duties because of its obsolescence.
Despite being a better fighter than the P.11, there were few acquired by the Polish Air Force, which preferred to wait for the PZL.50. When it became clear the PZL.50 would not be ready in time to counter the imminent German attack, the PAF resumed production of the P.11 and ordered the P.24. However, no PZL.24s were produced before the war started, and only two were used in the Polish Campaign. Polish Air Force had one PZL P.11g Kobuz which was used during Invasion of Poland. This aircraft, piloted by H. Szczęsny shot down two German aircraft on 14 and 15 of September. Usually this aircraft is identified as a P.24.