Nur Nadir, who at 28 is 43 years her husband's junior, said she would fight to "rectify the wrongs" of the British justice system in locking him up.
Speaking outside the Old Bailey, she said he was a "warm and wonderful man" whose Polly Peck business had benefited tens of thousands of people around the world.
She added her husband was a "business genius" and his wealth was a "direct result of his and his family's working morals and ethics".
Polly Peck collapsed in 1990 owing £550 million and Nadir was due to face trial in 1993 but he fled to his native Cyprus where he remained for 17 years.
He returned to Britain in 2010 confident he would be cleared but a jury this week found him guilty of stealing £28.6 million, the equivalent of £61.8 million today.
