It follows last month’s arrests of four Vietnam Airlines cabin crew found with the tubes in carry-on bags after a flight from Paris to Ho Chi Minh City.
They said they were hired to transport 60kg of toothpaste but didn’t know it was ecstasy, ketamine and cocaine.
Vietnam is a major drug-trafficking hub despite having some of the harshest drug laws in the world.
About half of the 327 toothpaste tubes the flight attendants were transporting contained drugs. Investigators said the women were unaware of their contents – they are currently out on bail.
Police said this week that the 65 suspects had been arrested after they uncovered another six shipments of narcotics being smuggled into Vietnam via the same route.
It is alleged they were directed by the same smuggling ring that hired the flight attendants.
The 65 suspects are being investigated for various charges, including buying, selling, transporting and storing narcotics, local media reported.
Police suspect the same syndicate often uses Vietnamese nationals studying and living in France to bring drugs into the country.
Once the drugs arrive at Vietnamese airports, domestic delivery services transport them to an accomplice in Dong Nai province bordering Saigon.
The drugs are then transported to multiple localities for distribution.
Authorities say the amount of drugs seized via air routes into the country over the past three months has surpassed the amount of airborne drugs trafficked in the past five years combined.