Sheikh Hamad bin Khalifa Al Thani is expected to launch a $254 million construction project to help rebuild the war-torn Palestinian territory.
Qatar has become one of Hamas’s main benefactors since it fell out with Syria and has had a rift with Iran.
The Palestinian Authority expressed reservations about the emir’s visit.
Sheikh Hamad flew to Egypt and crossed into Gaza by car amid tight security.
The Hamas interior ministry said it had a “well-prepared plan” to protect the emir, deploying thousands of security personnel and blocking roads to Gaza City’s stadium, where he is expected to address a crowd.
Earlier, the Israeli military said a soldier had been wounded by a bomb explosion along Israel’s border fence with Gaza, near Kissufim.
The visit is a sign of the increasing ties between the Gulf state and Hamas.
Qatar, one of the richest countries in the Arab world, has become an important source of revenue for Hamas in the aftermath of its fallout with Syrian President Bashar al-Assad.
In February, Hamas announced that its political leadership had been moved from Syria to Egypt and Qatar, because it could no longer effectively operate because of the unrest in its long-time ally.
The political bureau of Hamas had been based in Damascus since 1999, and relations appeared to be good until anti-government protests erupted throughout Syria in March 2011.
Hamas initially neither publicly endorsed the Syrian government’s handling of the uprising nor repudiated it.
Analysts said the Sunni Islamist movement was torn between risking the financial backing of Syria and its ally, Iran, and supporting Syria’s majority Sunni community, which has borne the brunt of the crackdown by the Alawite-dominated security forces.
But in February, the head of the Hamas government in Gaza, Ismail Haniya, declared his support for “the heroic people of Syria who are striving for freedom, democracy and reform”.
Qatar, meanwhile, was the first Arab nation to call publicly for military intervention in Syria to topple the government.
It was the main Arab player in the NATO-led coalition in Libya and has played a major part in trying to resolve regional conflicts.
The country maintains cordial relations with both the US and Iran, and – even more unusually for an Arab state – with both Hamas and Israel.
Most recently, Qatar has been involved in the reconciliation process between Hamas and its long-time rival faction, Fatah, which dominates the Palestinian Authority and is in power in the West Bank.
Hamas, which won parliamentary elections in 2006, ousted forces loyal to Palestinian Authority President Mahmoud Abbas in Gaza during clashes in 2007 and set up a rival government.
In response, Israel tightened its blockade on the coastal territory, which has had a crippling effect on Gaza’s economy.
A spokesperson for Mahmoud Abbas said the Palestinian Authority welcomed Qatar’s efforts to help the people in Gaza but also stressed “the necessity to preserve the legitimate representation of the Palestinian people”.
Mahmoud Abbas called on Sheikh Hamad to “urge Hamas in Gaza to go for reconciliation and to end this split”.
Image source: Wikimedia Commons President-elect Donald Trump celebrated his election victory at the Ultimate Fighting…
Millions of voters across the US chose to return Donald Trump to the White House…
Donald Trump declares victory in the US election as he addresses jubilant supporters in Florida.…
Stocks around the world are rising as Donald Trump appears to be on the cusp…
Donald Trump has won Pennsylvania, North Carolina and Georgia and taken a lead over Kamala…
Quincy Jones, the celebrated musician and producer who worked with Michael Jackson, Frank Sinatra, Ray…