The Israeli army dropped Taha Dwaik, a resident of the West Bank city of Hebron, near the Jewish settlement of Netzarim, from where he made his way to Gaza City, said Palestinian security sources on Thursday.
Israel's supreme court on Wednesday authorised the army to expel Dwaik, who was being held in administrative detention.
Detainees held in administrative detention are held without trial or charge, a move criticised by human rights groups. Dwaik is married and the father of four children.
Another two West Bank Palestinians have been expelled to Gaza since Monday. They form part of a group of 18 Palestinians ordered expelled by the army in mid-October.
Palestinians have protested that the expulsions are in violation of Article 49 of the Geneva Convention banning the forced transfers of individuals or groups living under occupation.
But the supreme court argues they are being displaced and not expelled.
Palestinian President Yasir Arafat has previously warned that Israeli deport plans mark the start of a wider policy of transferring Palestinians from their homes.
A policy long championed by many in Israel's radical right,
"transfer" would see the estimated 1.5 million Palestinians in the West Bank and Gaza Strip moved to neighbouring Arab states.
Apartheid wall extended
Meanwhile, Israel began construction on another section of its barrier cutting off parts of the occupied West Bank close to the heavily-populated Alkana Jewish settlement.
Palestinians fear wall will mark
borders of a future state
Three bulldozers, guarded by armed vigilantes and soldiers, began to level the land near the Palestinian village of Rantis which lies around 30km west of Ram Allah on Thursday, according to witnesses.
The 7.4km section will run from Rantis, which is several hundred metres on the Palestinian side of the Green Line marking the boundary of the West Bank, southwards to the Palestinian village of al-Midia.
The mayor of al-Midia, Talab Sabaka, said that "the army has put up placards around our village telling residents about the construction”.
The village faced the loss of 250 hectares of farmland as a result of the work, said Sabaka.
Construction of the apartheid wall was approved by the Israeli cabinet last month.
Israel says it is constructing the barrier to prevent resistance fighters from infiltrating its areas and carrying out anti-occupation attacks. But Palestinians fear the wall will demarcate the boundaries of a future Palestinian state.
The wall slices off some of the most fertile territory of the West Bank.
The barrier was overwhelmingly condemned in a vote by the United Nations General Assembly last month but the Israeli government made clear that it had no intention of paying heed to a non-binding resolution from a body which it considers to be as systematically hostile.
A report released on Tuesday by the UN Office for the Coordination of Humanitarian Affairs (OCHA) noted that the barrier only conforms to Israel's recognised boundary on 11% of its planned route.
The report said that it would thus effectively annex 15% of the West Bank and lead to severe humanitarian consequences for more than 680,000 Palestinians.
“Little consideration appears to have been given by the Israeli government to the wall's impact on Palestinian lives," the report said.