The state-run Korea Institute for Defense Analyses is in the final stage of research on the issue, and based on the results, the ministry could begin procedures to revise the military service act as early as next year, the official said.
Currently, naturalized South Koreans can join the military, if they choose, while all able-bodied South Korean men are required to carry out compulsory military service for about two years in a country that faces North Korea across a heavily fortified border.
"(The revision) is an issue that has been actively raised by the defense ministry to strengthen the sense of duty and responsibility of the naturalized citizens, and consider fairness in military service between the natives and the naturalized," a military manpower administration official said.
About 1,000 people aged 35 or under become naturalized as South Korean citizens every year, and a vast majority of them are known to be ethnic Koreans from China.
A government official said a detailed revision plan will be prepared to make sure that the naturalized citizens subject to draft are suited to join the South Korean military.
The law revision plan comes as the number of people required to serve in the military is projected to fall to 225,000 in 2025 before dropping to 161,000 in 2038, compared with 360,000 in 2016.
Earlier in the day, South Korea said it will reduce its number of troops to 500,000 by 2022. In 2018, South Korea has 599,000 troops, according to the 2018 defense white paper. (Yonhap)