Omri Sharon pleaded guilty in November to falsifying corporate documents, perjury and violating party funding laws. Under a plea deal, prosecutors dropped charges of fraud and breach of trust but demanded imprisonment on the other counts.
He resigned his parliamentary seat in January, in anticipation of the sentencing. Ariel Sharon, Israel's incapacitated prime minister, was not charged in the affair.
The charges carried a maximum of five years in prison.
Under Israeli law, a legislator convicted of an offence defined as one of "moral turpitude" loses his or her seat.
In sentencing the prime minister's son on Tuesday, the Tel Aviv District Court said Omri Sharon would be on probation for a further nine months in addition to his sentence and would have to pay a fine of 300,000 shekels ($64,000).
Israeli radio reports said he would not have to serve the prison sentence immediately because his father remained in a coma since suffering a devastating stroke on 4 January.
Omri Sharon's activities were meant to conceal illegal contributions during the 1999 campaign where his father won the chairmanship of the Likud party, becoming its ultimately successful candidate for prime minister in the 2001 national elections.
"I have made grave mistakes and I'm sorry about that"
Omri Sharon told the Tel Aviv court last month that he was inexperienced in politics when he began working to get his father elected as prime minister.
He said: "I have made grave mistakes and I'm sorry about that."