It found Vo Van Nam, Ngo Thi Cham and Chu Van Thang guilty of "illegal trading of narcotic substances."
In April last year Nam and Cham asked an unknown woman who lives in Laos to sell them methamphetamine at VND600 million ($25,690) per kilogram.
The woman arranged for two kilograms of the drug to be placed beneath an electric pole on Nguyen Van Cu Street of Hanoi's Long Bien District and for Thang to collect and deliver them to Nam. But Nam only had money for one kilogram and Thang was returning with the rest when he was arrested.
Vietnam had more than 222,000 drug addicts as of the end of 2017, with an increasing number of them, especially young partygoers, using synthetic drugs like meth, ecstasy and ketamine, according to the police.
Drug use is strictly prohibited in the country and users are fined and sent to rehab centers. Producing or distributing drugs is a crime that attracts the death penalty.
Vietnam is a key trafficking hub for narcotics from the Golden Triangle, an intersection of China, Laos, Thailand, and Myanmar that is the world's second largest drug producing area after the Golden Crescent in South Asia.