Former hunger striker Bilal Diab was released from Israeli jail to his home in the northern West Bank on Thursday, as part of an agreement to end his 77-day strike.
Diab, 27, told reporters he carried a message from Palestinians in Israeli jails to immediately end the factional division between Hamas and Fatah.
He also called for political leaders to work to free all prisoners, in particular those held before the 1993 Oslo Accords.
Hundreds of Palestinians gathered at the al-Jalama crossing in the northern West Bank to greet the released prisoner.
Diab, from Kafr Rai village near Jenin, said his delight at being released was diminished because of thousands of prisoners left behind.
He was detained in August 2011 given a six month administrative detention order, which was renewed in February.
Two weeks later, he began an open hunger strike against his continued detention without charge.
Diab agreed to end the strike in May in exchange for release when the detention order expired, as part of a wider deal with Israeli authorities after approximately 2,000 prisoners joined the hunger strikes.
Four Palestinians remain on hunger strike in Israeli prisoners, prisoners group Addameer says.
There are 4,706 Palestinians jailed in Israel, according to latest figures from Addameer.