The pause in fighting began at 7 am (05:00 GMT) in the Palestinian territories, silencing weapons that have raged since Hamas’s surprise attack outside Gaza on October 7.
More than 14,800 people have been killed in Gaza in Israeli strikes since October 7.
The Israeli regime intensified its attacks ahead of the pause in fighting, including an air strike that killed at least 27 people at a UN school on Thursday night.
Thirty-nine Palestinian prisoners held in Israeli jails and 13 captives in Gaza are expected to be released in the coming hours, with aid trucks also crossing into Gaza.
The Gaza Strip endured a night of intensified bombardment from “air, land, and sea” ahead of start of Qatar-mediated truce, UN said.
The first group of Israeli captives –13 women and children– will be released at about 4 pm local time (14:00 GMT).
The Red Cross will escort them to the Rafah border crossing and hand them over to the Israeli military who will begin the identification process, Al Jazeera reported.
The captives will be taken to hospitals in Tel Aviv for physical and psychological tests.
Thirty-nine Palestinian prisoners are also going to be released from Israel as part of the swap on the first day.
They will be taken from two Israeli prisons Damon and Megiddo, both southeast of Haifa. They will then be driven to the Ofer prison, south of Ramallah in the occupied West Bank, and from there to a nearby crossing and handed over to their families.
Much-needed humanitarian aid is also expected to cross from Egypt into Gaza in the hours that follow.
Hamas says 200 aid trucks and more trucks of fuel will enter Gaza daily.