Rear Admiral Konstantinos Kontogiannakos HN was born in Athens, Greece, on June 4th, 1966. He joined the Hellenic Naval Academy in 1986 and graduated in 1990 as Ensign of the Hellenic Navy. 

In January 2025, he was promoted to Rear Admiral.

He has served in combat units of Hellenic Navy as a Duty/Warfare/Division Officer, onboard HS SFENDONI (D-85), HS SACHTOURIS (D-214), HS AMFITRITI (S-117), HS TRITON (S-112) and as Executive Officer on HS GLAFKOS (S-110).

He served as Commanding Officer of HS PROTEFS (S-113) and HS NIREFS (S-111) and in Hellenic Navy Detachment in Kiel Germany, for the 214 class Submarine Program. 

He served as the Commissioning Commanding Officer on the first of 214 class submarine HS PAPANIKOLHS (S-120).

He served as head / responsible of works and sea trials of the new Type 214 and MLU HS OKEANOS, in Naval Shipyards of Skaramangas.

He served as Director of Submarines Program in Hellenic Navy General Staff Armaments Directorate.

He served as Chief of Staff and as Commanding Officer, of the Hellenic Submarines Command.

He served as Director of the General Director Office in General Directorate for Defense Investments and Armaments (GDDIA) of Ministry Of National Defence. 

He served as Director of the Third Brunch (Weapons, Electronics, Logistics Plans and Policy and Navy Infrastructure) of Hellenic Navy General Staff.

From February 2025 has assumed the duties of Chief of Staff of the Hellenic Navy General Staff.

Rear Admiral Konstantinos Kontogiannakos HN has passed through all the required career schools of Hellenic Navy and Armed Forces:

• Naval War College
• Supreme Joint Staff War College
• Hellenic National Defense College

He holds all required medals and commemorations for his rank.

He speaks English and French.

Rear Admiral Konstantinos Kontogiannakos HN is father of three daughters.