The number of people eligible for active-duty military service in South Korea has fallen by more than 130,000 over the past decade, as the country's shrinking pool of draftees accelerates amid a deepening low-birthrate trend. Analysts say concerns over a "manpower cliff" are becoming reality as the pool of active-duty enlistment candidates plummets.
According to reporting compiled by The Seoul Economic Daily on the 5th, the number of active-duty enlistment candidates stood at 322,674 as of Dec. 31, 2025, down 132,874 from 455,551 in 2016, a 29.2% plunge. The decline is equivalent to the disappearance of manpower for more than 10 divisions over the decade.
As of 2025, the average strength of a single South Korean military division is about 10,000 to 12,000 troops. The figure reflects troop reductions and unit restructuring under the Defense Reform 2.0 plan.
Active-duty enlistment candidates have plunged for 10 straight years, falling by an average of about 14,000 annually. An analysis of the "Military Manpower Statistical Yearbook" shows the figure declined continuously from 455,551 in 2016 to 435,358 in 2017, 418,913 in 2018, and 419,096 in 2019, before dropping into the 300,000 range for the first time in 2020.
The downward trend has continued, from 379,102 in 2020 to 345,501 in 2021, 345,501 in 2022, 339,214 in 2023, 328,508 in 2024, and 322,674 in 2025. If this trend continues, a drop into the 200,000 range by 2028, two years from now, appears inevitable.
An official on the National Assembly's National Defense Committee said, "As the shortage of military manpower deepens due to the worsening low birthrate, we must swiftly redesign our troops, units, and force structure." The official added, "We must meticulously prepare mid- to long-term measures to transition to a future military structure, including the introduction of a selective volunteer military system that the Lee Jae-myung administration seeks to pursue."
The materialization of the manpower cliff shaking the foundations of the armed forces becomes clear when examining the total military manpower pool (subject to conscription and mobilization), the base population for military resources.
The total military manpower pool also fell sharply, from 1,427,660 in 2016 to 923,444. Compared with the decline in active-duty enlistment candidates, it fell by 504,216 over the same 10-year period, shrinking the base population by 35.3%. With an average annual decline of about 50,500, the total military manpower pool has shrunk by more than four divisions each year.
The serious problem is the pace of the plunge in the total manpower pool. Over the same period, active-duty enlistment candidates fell by an average of about 14,000 annually, while the total manpower pool declined by an average of about 50,500 — a pace of decline roughly 3.7 times faster.
Military authorities maintain that the armed forces' standing troop strength still stands at around 500,000. However, the dominant analysis inside and outside the military is that it has fallen to the low 400,000 range. In reality, the force falls short of the minimum troop level required under an armistice (500,000) by as much as 70,000 to 80,000.
Moreover, the number of soldiers enlisting as active-duty troops has halved from 360,000 in 2000 to around 180,000 in 2025. For this reason, the Korea Institute for Defense Analyses (KIDA) forecasts that the pool of active-duty enlistment candidates will drop into the 200,000 range by 2028, and then, a decade later in 2038, fall into the 100,000 range, collapsing below the 200,000 mark.
Some point out that difficulties in securing manpower are pushing even resources unfit for active-duty service into active-duty enlistment. The argument is that the increase in active-duty determinations is a desperate measure to fill the shortage of active-duty manpower amid the dwindling pool of enlistment candidates.
In fact, the active-duty determination rate in the Military Manpower Administration's conscription examinations exceeded 50% in 1986, but has held at around 80% since 2003.
A KIDA researcher said, "The golden window to prepare for the plunge in military manpower caused by the ultra-low birthrate is only about 10 years." The researcher added, "We must urgently devise solutions to the shortage of military manpower, including extending the length of military service, abolishing supplementary service, and introducing a selective volunteer military system."
