Used in combat by Bulgaria (150), France, Italy (72), and Romania (96).
Battle of France
There were only 36 D.520s operational by May 10, 1940.
Only 36 Dewoitine D.520s were delivered to one groupe de chasse, the GC 1/3, by May 1940. This groupe shot down three Hs 126s and one He 111 on May 13, 1940.
43 Dewoitine D.520s were then delivered to the GC II/3, GC II/7, GC III/3, and GC III/6.
52 were then delivered to the Aéronavale escadrilles AC 1, 2, 3, and 4 before France surrendered.
It was clamed that the D.520 shot down 114 enemy planes by the time of the armistice. The D.520s also lost 85 of their own.
After the surrender of France, D.520s were used by the Germans as trainers.
In 1942 the Germans seized 411 (246) D.520s and passed them onto Axis countries.
Were used as combat aircraft. 235 D.520s were used by the Vichy air force in France and 202 were used in Africa.
Adjutant Pierre Le Gloan of GC III/6 shot down 18 aircraft. He shot an additional 4 in other aircraft.
After World War II
A few of the D.520s that remained were converted to two seat trainers. The last of the D.520s were withdrawn from service in September 1953. These were a part of the Escadrille de Présentation of the Armée de l'Air.