The licence allows the military-run company to launch 5G services in Hanoi and Ho Chi Minh City on a trial basis, the ministry said.
The work aims to evaluate technical features and the ability to deploy telecommunications infrastructure using the fifth generation (5G) mobile communications system - IMT 2020.
The company is not permitted to collect fees from its 5G users during the trial period, which will end on Jan 21, 2020.
Last year marked a milestone for Viettel when it founded cyber security and high-tech defence industries and declared plans to embark on the fourth development stage with the goal of going global and pioneering in the fourth industrial revolution.
Viettel has a significant presence in 12 countries and a customer base of more than 85 million subscribers across Asia and Africa.
It has also invested in research, manufacturing and successful commercialisation of strategic weapons, high-tech military equipment and telecom network equipment.
