Sous Lieutenant Émile Julien Mathurin Régnier (29 July 1894 – 4 September 1940) was a World War I flying ace credited with six aerial victories.
Régnier was born in Plémy, Brittany.
He served in the French infantry from September 1914 until early June 1917, suffering two serious wounds in the process.
On 28 June 1917, he transferred into aviation as a corporal.
After earning his pilot's license and undergoing advanced training, he joined Escadrille 89 as a fighter pilot on 8 January 1918.
He would serve through war's end, sharing in six confirmed victories scored in conjunction with other pilots.
Postwar, he would be granted the Légion d'honneur to add to his Médaille militaire and Croix de Guerre.
He became successively an agent for De Havilland beginning in 1932, then an air racing participant, and finally an aircraft engine designer and builder beginning in 1934.
He died at Pozzi, Valeggio sul Mincio, aged 46.
Régnier's death did not close down his aircraft engine company, which subsequently was captured and used by the Nazis during World War II.