Defense minister Phan Van Giang said at the National Assembly Friday that the number of people reaching the age of military service is high, but so are the numbers of exemptions and postponements, and as a result fewer and fewer people are being drafted.
All male citizens need to sign up for military service when they turn 18.
Those who enter university or college can postpone their induction but need to sign up before they turn 28.
But if they continue to get postponements until they turn 28, they can avoid induction altogether.
Other reasons for exemptions include having too many visible tattoos and severe myopia and hyperopia.
Women are not required to undergo military service, but can volunteer.
Giang said the law would be amended to limit the exemptions and postponements and reduce the service period from the current two years.
Some people have called for making the law as strict as in South Korea.
South Korea requires all male citizens to serve in the military for at least 21 months between the ages of 18 and 35, and failure could get one up to three years in prison and loss of citizenship in the case of dual citizens.