Loc Van Cat, 32, was caught trafficking 246 kg of drugs in a car in Cao Loc District on March 13.
Authorities later arrested 30-year-old Vy Van Hen, also in Cao Loc District, and 26-year-old Hoang Van Chinh in China's Ningming County, which borders Lang Son, for their connection to the case.
The suspects and the meth have been transferred to Lang Son Police for further investigation.
Vietnam has some of the world's toughest drug laws, including death for smuggling and trading, but drug busts continue to be a frequent occurrence.
Those convicted of possessing or smuggling over 600 grams of heroin or more than 2.5 kilograms of methamphetamine face capital punishment. The production or sale of 100 grams of heroin or 300 grams of other illegal narcotics is also punishable by death.