The Finola was loaded with heavier stock, weighing over 400 kilograms each, at a value of nearly $1.5 million.
Dean Ryan, from South East Asian Livestock Services, says the expanding market in Vietnam is a welcome relief for northern cattle producers.
"It's very important to producers in the Territory, because we've been limited for markets for our heavier, slaughter-type cattle," he said.
"We've been totally dependent on Indonesia for the last few years and to have a viable alternative is a great relief."
As of March 31 this year, nearly 46,500 cattle had been exported from Darwin Port. The vast majority of NT cattle have been exported to Indonesia, with Vietnam receiving the next largest share.