Police in the northern province of Thai Binh confiscated a 6.5-kilogram rhino horn from a car Tuesday.
A group of traffic police officers spotted the car traveling on National Highway 10 in Thai Binh City's Tan Binh Commune and signaled the driver to stop for an inspection.
They found the rhino horn wrapped in a plastic bag.
Hoang Van Dong, the 31-year-old driver, failed to produce papers to prove the origin of the horn.
Police confiscated the horn and detained Dong for further investigations.
In Vietnam, rhino horns are banned for trade by the government. They are also believed by many local people to have medicinal uses.
Research funded by the World Wide Fund for Nature South Africa (WWF-SA) that surveyed 720 people in Hanoi and Ho Chi Minh City this year showed that rhino horn consumers are wealthy and use the horn mostly to confirm their social status within Vietnamese society.