Former Politburo member Dinh La Thang was found guilty of economic mismanagement over losses in state oil firm PetroVietnam.
The trial is part of a showcase crackdown on corruption involving high-profile energy and banking executives.
Another executive from the firm, Trinh Xuan Thanh, was sentenced to life.
His case came to international attention last year, when the German foreign ministry accused Vietnam of illegally kidnapping him from Berlin, where he was seeking asylum.
The trial is seen by some as a showcase of the Communist Party’s fight against corruption.
But correspondents say it is also seen by some as a purge of opponents of leading Party officials.
Twenty other people were sentenced on Monday at the trial in Hanoi, which was closed to foreign media.
They received jail terms ranging from three years suspended to nine years. (Courtesy BBC)