As a captain, with Lieutenant Bruno Heluin (platoon leader) as the company commanding officer, he led an assault at the Battle of Vrbanja Bridge in 1995 that was the latest fixed bayonet charge of the French Armed Forces.

His father, Yves Urbain Marie Lecointre (5 April 1932 – 17 July 1985), was a French naval officer and submariner who served as the commandant of SNLE Le Redoutable.

Under the orders of General Hervé Gobilliard and Colonel Erik Sandahl, Lecointre and Lieutenant Bruno Heluin led a bayonet charge to win the Battle of Vrbanja Bridge on 27 May 1995.

[13] From 1996 to 1999, Lecointre was an instructor at the École spéciale militaire de Saint-Cyr in Coëtquidan, Morbihan where he trained student officers in military tactics.

On 20 July 2017, Lecointre was appointed Chief of the Defence Staff by President Emmanuel Macron, following the resignation of General Pierre de Villiers;[20] he was promoted to the rank of Général d'armée.

[21] On 21 July 2021, Lecointre retired from active service and was succeeded by General Thierry Burkhard as Chief of Defence Staff.