LCDR Hyeyeon (Leo) Yi currently serves as the CNWMD Security System Officer at the Republic of Korea (ROK) Joint Chiefs of Staff. A 2008 graduate of the ROK Naval Academy, LCDR Yi began his career as a Communication Officer aboard a ROK logistics support ship. He subsequently served as Combat Information Officer on a Patrol Combat Corvette (PCC) and as Deck Officer on a Frigate (FF) in the ROK 1st Fleet, experiences that laid a strong foundation for his naval career.
After his promotion to Lieutenant, he commanded a Patrol Combat Medium (PKM) vessel, leading missions near the Northern Limit Line (NLL) and maintaining readiness against North Korean naval threats. He then served as Aide-de-Camp to the ROK Fleet Commander, where he gained valuable insights into the close ROK-US alliance.
In 2015, LCDR Yi became the Anti-Submarine Warfare Officer aboard an advanced Aegis Destroyer (DDG), participating in operations with the US Navy, including North Korean ballistic missile search and track missions. He furthered his expertise by earning a B.A. in International Relations (National Security Policy) from Korea National Defense University in 2017, where he researched regional security dynamics and received an award from the Chief of Naval Operations for academic excellence.
In 2019, LCDR Yi was selected as the Combined Operational Officer for the Escort Task Group (ETG) and deployed to the Gulf of Aden, conducting merchant ship convoys and maritime security operations with international partners such as CMF, CTF-151/152, and EUNAVFOR. He continued his professional development in 2020 as a student at the Commander and General Staff Course, publishing a paper on China’s stance toward North Korea’s nuclear development, and later served as an operations planner for the ROK Fleet.
In 2022, LCDR Yi was appointed as Aide-de-Camp to the Minister of National Defense, gaining extensive experience in military policy, security strategy, and international relations, particularly with the United States. He participated in high-level ministerial talks at the Pentagon, the Shangri-La Dialogue in Singapore, and the ASEAN+ Dialogue in Cambodia, strengthening relationships with U.S. representatives and other international partners.
