Gaza's Health Ministry says a 15-year-old Palestinian boy was killed by Israeli army fire during a protest near the perimeter fence with Israel.
The ministry said early Thursday that Moumin Abu Eiada was shot in the head as he participated with dozens in an overnight protest in southern Gaza.
After months of weekly marches along Israeli frontier, Hamas has accelerated the pace of protests in recent days.
The Israeli military said earlier there had been several incidents along the Gaza-Israel border on Wednesday "with the participation of hundreds of rioters" who rolled burning tyres and hurled firebombs and rocks at soldiers. It said there were no Israeli casualties.
On Tuesday two Palestinians were shot dead during violent protests next to the Erez crossing into Israel.
Demonstrators are calling to be allowed to return to the homes their families fled from in 1948, which are now inside Israel.
For months, the marches were limited to Fridays but Wednesday's protest was the third this week, with new grounds including Gaza's northwestern tip at the Mediterranean where land and sea boundaries converge. On Tuesday, Palestinian protested outside Erez, the only crossing point for people into Israel or the West Bank.
"This thunderous march will not stop until the ordeal is over. This is our resolution," Hamas chief Ismail Haniyeh said during the funeral of a Palestinian killed a day earlier at a protest.
At least 182 Palestinians have been killed in the protests, according to Palestinian health officials.
At the protests, Palestinians burn tires, hurl rocks and sometimes firebombs at Israeli forces and snipers perched atop earthen mounds behind the boundary fence. For some time, protest activists sent incendiary kites and balloons across the fence to set fire to Israeli farmland.
The Israeli army says it is defending its border against rioting protesters who have sought to breach the fence and enter Israel.
Israel withdrew its troops and settlers from Gaza in 2005 but maintains tight control of its land and sea borders and has fought three wars there in the past decade against Hamas Islamist militants who control the territory.
With Egypt, Israel has imposed a blockade that the World Bank says has brought Gaza's economy to crisis, leaving its two million people with limited access to healthcare, clean water and electricity.
Peace talks between Israel and the Palestinians have been stalled since 2014.
Hamas hopes to press Israel and Egypt into lifting a blockade they imposed on Gaza when the militant group took control in 2007. The group has accused its main political rival, the West Bank-based Palestinian Authority, of thwarting Egyptian-mediated efforts for a deal with Israel.