They had transported across the border goods that were not well preserved and deteriorated, according to the Lao Cai Economic Zone management.
Buyers and sellers have been unable to reach agreement on compensation and therefore the trucks have not been allowed to return home.
Some other trucks are also stuck across the border because buyers and sellers disagreed over how to carry out contract terms.
The zone management said Vietnamese authorities have been trying to resolve these issues unsuccessfully.
Vietnamese and Chinese businesses need to make more explicit contracts to ensure a healthy business relationship, but Vietnamese businesses admittedly need to improve product quality, it added.
Last year US$2 billion worth of goods passed through the Lao Cai Border Gate, a 39% increase from 2022.
China has increased the import of Vietnamese agriculture produce this year, especially durian.