South Korea’s standing military has fallen to about 450,000 personnel, a sharp drop of more than 110,000 troops compared with 2019, according to newly disclosed government data.
The figures, obtained from the Ministry of National Defense and the Military Manpower Administration by Rep. Choo Mi-ae of the National Assembly’s Legislation and Judiciary Committee, highlight both the scale of recent restructuring and the challenges ahead for maintaining force readiness.
As of July 2025, the number of active-duty service members has decreased from 563,000 six years earlier.
The Army has borne the brunt of this reduction, losing more than 100,000 troops over the period. Officials confirmed that 17 divisions and other large units have been disbanded or merged, reshaping the country’s ground forces.
The impact has been felt most in Gangwon and Gyeonggi provinces, regions along the border with North Korea, where several combat formations have been consolidated or dissolved. Analysts warn that remaining units now face wider defensive responsibilities, raising concerns over operational responsiveness should a crisis occur.
Recruitment has also become more difficult. The selection rate for career officers has dropped to roughly half of past levels, making it harder to secure long-term service members. Defense officials cite South Korea’s record-low birthrate as the primary cause of the shrinking pool of conscripts. They acknowledge that the demographic problem is structural and expected to deepen in the years ahead.
In response, the defense ministry has considered measures to slow the decline, including expanding recruitment of women, offering bonuses for short-term service, and reducing the number of men assigned to noncombat supplementary duties. Critics argue, however, that these steps are unlikely to offset the long-term shortage.
A senior official from the defense ministry, speaking on condition of anonymity, said advanced systems and better training could help compensate for smaller forces but cautioned that technology cannot completely replace manpower.
“There are limits to replacing people with technology, especially when facing a heavily armed adversary right across the border,” the official said.
The decline comes at a time of heightened regional security challenges. North Korea continues to expand its nuclear and missile programs, underscoring the importance of conventional deterrence. Experts note that without credible alternative capabilities and strengthened cooperation with the United States, a smaller ground force could create vulnerabilities.