Pavlo Lazarenko, the former Ukrainian prime minister, was sentenced to nine years in prison and fined $10million in a US court on Friday.
He had been convicted of extortion and money laundering in 2004.
Martin Jenkins, a US district judge, said before pronouncing the sentence: "A significant sentence is appropriate."
He is the first former foreign leader to be sentenced in a US court since Manuel Noriega, the leader of Panama, in 1992.
Lazarenko was prime minister from 1996 to 1997.
A jury convicted him of 29 counts of extortion, laundering money, fraud and transportation of stolen property.
Jenkins later threw out 15 counts, finding that there was not enough evidence to sustain convictions on those charges.
The complex case involved many firms and banks and various countries, including Ukraine, Poland, Hungary, the Netherlands, Switzerland and the US. US prosecutors spent six years building the case.
US prosecutors had sought a sentence of more than 18 years, plus restitution of more than $43million and forfeiture of nearly $23million.
They wrote in their sentencing memorandum: "The defendant's conduct was egregious - he misused his office to generate tens of millions for himself at the expense of the Ukrainian people and then sought to avail himself of our banking system to safeguard his criminal proceeds."
Lazarenko has been kept under house arrest in a San Francisco apartment since 2003.
Jenkins said he would rule on the restitution and forfeiture issues in the next 90 days.
As he left court Lazarenko said: "I await the appeal. Over the past year and a half, we have been fully preparing for the appeal, going over all the transcripts and the details."