Husayn Mahmud Awad was pronounced dead on Friday by doctors at a hospital in Ram Allah where he had been transferred for treatment after being struck in the head by a bullet fired at the protest in the central occupied West Bank.
About 100 protesters, mostly youths, had gathered at the protest after Friday prayers before beginning to throw stones, an AFP photographer witnessed.
A military source said rubber-bullets and tear gas had been fired at the protesters after they hurled rocks and Molotov cocktails at construction workers and soldiers.
Israeli Prime Minister Ariel Sharon told US President George Bush this week he would speed up work on the barrier, arguing it is "essential in order to ensure the security of the citizens of Israel" from would-be Palestinian attackers.
Palestinians say the route of the barrier, often jutting deep into their land, shows it is more akin to a land grab and an attempt to pre-empt the borders of their promised future state.
The latest death brought the overall toll since the September 2000 start of the Palestinian uprising to 3905, including 2938
Palestinians and 898 Israelis, according to an AFP count.
Also on Friday, Aljazeera correspondent in the West Bank reported that Israeli military vehicles stormed Tulkarm refugee camp and then imposed a curfew on the people there. "Occupation forces took hold of four buildings and staged themselves on the rooftops," reported our correspondent.
Meanwhile, Israeli police imposed restrictions on people heading for al-Aqsa mosque to perform Friday prayer.
"Additional forces were deployed in the vicinity of the mosque and the Old City," reported the correspondent. "The forces announced they would not allow people under 45 years to enter the al-Aqsa Mosque", he added.