Franz Dörr was born on 10 February 1913 in Mannheim. During Invasion of Poland and Battle of France Dörr served as a reconnaissance pilot. In spring 1941, Feldwebel Dörr was transferred to 1.(Erg.)/Jagdgeschwader 3 (JG 3), based in theNetherlands. He claimed his first victory on 29 September 1941, when he shot down a Royal Air Force (RAF) Vickers Wellington twin-engine bomber.

On 1 January 1942, 1.(Erg.)/JG 3 was redesignated 7./Jagdgeschwader 5 (JG 5) and relocated to the Northern front. By the end of 1942, Dörr had increased his victory total to 12. He claimed his 20th victory on 18 August 1943. Dörr was appointedStaffelkapitän of 7./JG 5 on 14 September 1943. By the end of 1943, Dörr had accumulated 37 aerial victories. May 1944 was to see Dörr begin an amazing series of victories: six victories on 16 May, four on 25 May, five on 26 May, four on 15 June, eight on 17 June, five on 27 June, seven on 28 June, five on 4 July and four on 17 July.

Oberleutnant Dörr was awarded the Knight’s Cross of the Iron Cross on 19 August 1944 for 99 victories. On 1 August 1944, Dörr was appointed Gruppenkommandeur of III./JG 5. He claimed another six victories on 23 August to record his 100th through 106th aerial victories. In October 1944, Dörr claimed 22 Russian aircraft shot down, including six on 9 October and five on 21 October.

Franz Dörr survived the war. He died on 13 October 1972 in Konstanz.

During World War II Franz Dörr was credited with 128 victories in over 437 combat missions. All but one of his victories were claimed over the Eastern Front, including 16 Il-2 Stormoviks.