Vietsovpetro, the producer of about one third of Vietnam's total crude output, said it may need to stop drilling at some rigs if oil prices continue to plummet this year.
CEO Tu Thanh Nghia said at a meeting Tuesday that the venture will also call off exploration activities if necessary.
Oil producers around the world are grappling with the question of whether to cut back or increase production as falling oil prices start to take a toll on their profits.
The price of Brent crude has fallen by more than half since the middle of last year, to below US$50 a barrel this week.
OPEC said it would keep output unchanged, a move that many say was meant to stifle competition from emerging producers.
Figures from Vietsovpetro showed that the company turned out 5.36 million metric tons of crude last year, exceeding its target by 260,000 tons, and more than 1.4 billion cubic meters of gas.
It plans to produce 5.1 million tons of crude this year, down 5 percent.