Commander Gregory Guiran joined the French naval academy in 1997. Upon completion of the officer course, he specialized in anti-submarine warfare (ASW). Then, he furthered his career both on surface and submarine forces (nuclear powered and diesel).
In 2000, he first chose to be assigned as deck officer aboard the Estienne d'Orves-class corvette Lieutenant de vaisseau Le Henaff.
In June 2002, he joined the submarine forces and the SSN Saphir where he successfully carried out three operational patrols, fulfilling his mission as head of the deck and communication services.
He headed the underwater warfare service aboard the SSN Emeraude in 2005 and worked as head of the operations service aboard the SSN Perle a year later.
In September 2007, he was designated to cooperate on the Malaysian submarine project. He served as operations officer on the Scorpene-class SSN Tunku Abdul Ramhan and took part in its first at sea trials. He was also an advisor, within a group of experts, in the naval base of Sepengar Bay during one year.
In 2010, he returned to the surface warships with a three-year posting aboard the anti submarine warfare frigate Jean de Vienne as deputy crew commander then as operations commander.
During this assignment, he took part in the operation « Harmattan » in Lybia and has been involved in twenty-two combat actions.
In 2013, as battle watch captain, he worked within the Task Force 473, during the « Bois Belleau » deployment.
From July 2014 to January 2016, he assumed command of the French mine hunter Lyre. Throughout this period, he contributed to a dozen of mine clearance operations including six Second World War German mines.
Before integrating the 24th class of the French armed forces staff college, he returned to the Task Force 473, on the aircraft carrier Charles de Gaulle for the operation « Chammal ».
In summer 2017, he was assigned to the navy military personnel department, where he was in charge of monitoring human resources flows (recruitments and departures).
He held this position until 2019 and was promoted to the human resources branch of the ministry of the armed forces as deputy head of the human resources policy office.
Since September 2020, he is the commander of the command and supply ship Somme.
He holds various decorations and awards, including Knighthood of the Legion of Honour.
Commander Gregory Guiran is married with two children.