The 49-year-old Lee, who is the heir to one of the world's largest companies, was also found guilty of perjury, embezzlement, and of hiding assets outside of South Korea following a six-month trial.
Prosecutors argued Lee paid or promised to pay a total of 43.3 billion won ($38.4 million) in return for actions including government support for the scion's hereditary succession at the Samsung group.
But Lee, vice-chairman at Samsung Electronics and the Samsung founder's grandson, had said he was unaware of the donations, which were overseen by other executives. "In the appeal, we are certain to have all charges proven not guilty".
Lee's sentence is the most current in a scandal involving millions of South Koreans protesting last year, leading Park to be removed from the officer in March earlier this year. The appeal is expected to make its way through South Korea's legal structure, all the way to the Supreme Court, though that's not likely to happen until sometime in 2018. Park has denied all wrongdoing and has blamed Choi for ruining their friendship.
"The entire verdict is unacceptable", Song said, adding that he was confident his client's innocence would be affirmed by a higher court.
Also known as Jay Y. Lee, the executive is technically the "chaebol's" Vice Chairman, but he's been running the company for a few years now after his father suffered a heart attack. Two other Samsung executives were found guilty in the same trial and sentenced to four years in prison. Experts previously told CNBC that whatever verdict comes down on the Samsung heir, it will not affect the day-to-day business at Samsung.
In the past, several corruption cases against owners of these chaebols have been suspended or these tycoons were sentenced to only light prison terms, citing their contribution to the South Korean economy. This scandal let to the impeachment of Park, who is also facing her own corruption trial later this year.
Shares of Samsung Electronics closed down 1.05 percent, following the news.