An army spokeswoman said the closure had been lifted on Friday, allowing Israelis free access to the area.
The closure was imposed on Thursday after clashes with ultra-radical Jews resisting the planned pullout from the territory, the army said.
Security sources said the decision to prevent Israelis other than residents, from entering all 21 Gaza settlements on Thursday was intended to prevent an additional influx of radicals who have attacked Palestinians and security forces in the area in the past few days.
The lifting of the order came after a hotel was evacuated by Israeli troops in Neve Dekalim, the army said in a statement.
Israeli forces stormed a hotel where extremists were holed up and removed them all in minutes - an unplanned dress rehearsal for the August pullout.
The operation targeted the most dangerous of the opponents - West Bank extremists, some with long records of violence, who said they would battle against the Gaza pullout to the death.
But they were quickly overwhelmed by security forces, struggling and shouting as soldiers lifted them from the floor of the hotel dining room and carried them outside.
"You're expelling Jews like the Germans, like the Russians," shouted West Bank hardliner Nadia Matter at the soldiers, who ignored her as TV cameras recorded her words.
"You're expelling Jews like the Germans, like the Russians"
West Bank resident
Israeli Defence Minister Shaul Mofaz called the Jewish extremists "hooligans" and added: "Preparations for disengagement and the disengagement itself will go ahead as planned with no hesitation. This is a test of the nation's authority, and the nation will pass the test with honour."
In tandem with the lifting of entry restrictions, the Israeli army's senior commander in the area ordered a limit on the number of goods and belongings being brought into the area to enable an extended stay by settlers.
"The ... order will limit the ability of persons entering the Gaza Strip, both residents and non-residents, to transfer various types of equipment ... aimed at opposing the evacuation that is to be carried out as part of the disengagement plan," the statement said.
Israel's plan to evacuate all 21 Gaza settlements and four of 120 in the West Bank is set to begin in August, a plan US-led mediators hope will revive Israeli-Palestinian peace talks.
Settlers protesting at Israel's planned withdrawal almost killed a Palestinian boy at the Mawasi locality in the Gaza Strip on Wednesday.
TV footage showed settlers hitting the boy, Hilal Majaydeh, 16, with stones on the head.
Settlers attacked a 16-year-old
Majaydeh suffered serious head injury and concussions and was in critical condition.
The attack took place in full view of Israeli soldiers and was shown on television screens around the world.
Amram Mitzna, a former army commander of the southern West Bank and one of the Labour Party's most prominent leaders, described the behaviour of the soldiers as "vile and disgraceful".
"This is a disgraceful behaviour. If a Jew was being lynched, the soldiers would kill the Palestinian perpetrators without asking any question," Mitzna told the Israeli public radio, Reshet Bet, on Thursday morning.
The Palestinian Authority strongly condemned the "manifestly criminal act", calling on the Israeli government and army to stop these "criminal thugs".
Aljazeera.net's Khalid Amayreh in the West Bank contributed to this report