Said Naffa traveled in 2007 to Syria, with which Israel is technically still at war, as part of a delegation of 300 Druze religious leaders, the charge sheet said.
Naffa, a member of Knesset at the time, met a leader of the PFLP-General Command, an offshoot of the Popular Front for the Liberation of Palestine, which "is a terror organization," according to a ministry statement.
He initially denied the meeting took place and then said it was an arbitrary encounter, but "the court determined it was a secret and planned meeting, which could harm the state's security," the ministry said.
The Nazareth district court sentenced Naffa to one year for "contact with a foreign agent" and another six months for organizing and participating in the trip, the statement said, with the sentences to be served concurrently.
Naffa told AFP the trip was aimed at "reestablishing contacts between members of the Druze community in Israel, Syria and Lebanon."
He said he had appealed the verdict to the Supreme Court.
Israel's Foreign Minister Avigdor Lieberman welcomed Naffa's conviction.
He said in a statement it sent an "important message which will force those who want to make contact with enemies of the state and who publicly support terrorist organizations think twice."
Israel has 130,000 Druze citizens out of a population of around eight million. Unlike other Arab citizens of Israel, they are subject to the country's mandatory military service laws.
The Druze are native to parts of central Lebanon and southern Syria, and the Golan Heights.