Saudi Arabia pledged $1bn and Qatar $250m, while $174m will come from the United Arab Emirates, although they have not yet specified who they will pay the money to, or how it will be spent.
Japan, Italy and Turkey were among other nations who made multi-million dollar pledges to the PA.
Opening the conference, Hosni Mubarak, the Egyptian president, urged donors to give generously but said aid would not compensate for the 1,300 Palestinian lives lost during the war.
"I reach to you with an appeal from the heart to declare tangible pledges," he said.
Up to 75 countries and international organisations were asked to fund a $2.8bn reconstruction plan designed by Salam Fayyad, the Palestinian prime minister.
Fayyad wants a large part of the money to be channelled through the PA, which is based in the Israeli-occupied West Bank.
It remains unclear how the planned reconstruction of Gaza will be undertaken.
Todd Baer, Al Jazeera's correspondent in Gaza City, said that people living in the stricken territory are in desperate need of building supplies to rebuild their homes.
"How the pledges are going to reach Gaza is the big question here, if all the [donations] go to the PA in the West Bank and none to Hamas, which controls the Gaza Strip," he said.
"A number of officials from the United Nations, various non-governmental organisations and the World Bank have said that the money could be funnelled through them, to get into the Gaza Strip. That would be the most likely avenue."
The Gaza Strip is controlled by Hamas and Israel has said it will refuse to approve projects that could benefit the group.
"We definitely don't want to see the goodwill of the international community exploited by Hamas and serve Hamas's extremist purposes," Mark Regev, an Israeli government spokesman, said.
Hamas took full control of Gaza in June 2007 after driving out security forces loyal to Mahmoud Abbas, the Palestinian Authority president and leader of the rival Fatah group.
Hamas, which had not been invited to the conference in Egypt and is labelled a "terrorist" group by the US and the EU, has prepared its own reconstruction plan.
"We are welcoming anyone who wants to reconstruct Gaza, but without any political terms on Hamas or on the Palestinian people," Osama Hamdan, a Beirut-based Hamas official, told Al Jazeera.
Israel's blockade of the territory continues to prevent supplies, including construction materials, from crossing into Gaza.
The Ramallah-based Palestinian Authority (PA) says $2.8bn is needed to rebuild Gaza
A total of $3bn has been already been pledged by countries and entities including the European Commission ($554m) Saudi Arabia ($1bn), Qatar ($250m), Algeria ($100m) and the US ($900m).
The US says its financial assistance cannot be channelled through Gaza's Hamas-run government
Israel has barred entry into Gaza of material which it says may have a military use, such as cement and steel rods
Ban Ki-moon, the UN secretary-general, said border crossings into Gaza must be reopened to allow aid into the devastated territory.
"The situation at the border crossings is intolerable. Aid workers do not have access. Essential commodities cannot get in," he told donors.
"Our first and indispensable goal is to open crossings."
Marc Gopin, from the Institute for Conflict Analysis and Resolution at George Mason University, told Al Jazeera: "They can't even get in humanitarian aid at this point because the [Israeli] blockade is so severe," he said.
Abbas said that aid would be insufficient to meet Gazans' needs as long as there was no political settlement to the conflict.
"We appreciate your presence and the financial, economic and technical support that you are giving to the Palestinian people, but we insist on the pressing need to achieve substantial progress towards a just settlement [with the Israelis]," he said at the donor conference.
The Israeli assault on the Gaza Strip ended after Israel called a halt to the fighting on January 18. Hamas announced its own ceasefire the following day.
More than 1,300 Palestinians, including women and children, died during the war on Gaza, which Israel launched with the stated aim of preventing rocket fire from fighters based in the coastal territory.
At least 13 Israelis, three of them civilians, were also killed.
However, rocket fire has continued and Ehud Olmert, the outgoing Israeli prime minister, on Sunday vowed a "painful" response if the attacks on southern Israel did not stop.
Hillary Clinton, on her first visit to the Middle East since becoming the US secretary of state, said that US aid to the Palestinians would be part of a broader effort to achieve peace in the region.
"Only by acting now can we turn this crisis into an opportunity to move us closer to our shared goals," Clinton said in prepared remarks for the conference.
She confirmed the funds would not be channelled through the Hamas government in Gaza.