The two-day conference, labelled "a world in danger", is co-sponsored by Wiesel's New York-based Foundation for Humanity and brings together politicians, scientists, economists and humanitarians.
The 44 participants include 25 Nobel Prize winners and 19 international figures, among them, actor Richard Gere.
Nobel laureates attending include Israeli Vice Prime Minister Shimon Peres, VS Naipaul, the Trinidad-born British author and Wiesel, a Holocaust survivor and the 1986 Nobel Peace Prize winner.
Topping the agenda are discussions on poverty, disease and violence and ways to foster international efforts to build "tolerance, peace, justice and coexistence", according to a statement issued by Jordan's royal palace.
Jordan's King Abdullah II told delegates in his opening speech that humanity was at a "critical crossroad" and that the "direction we go is especially critical for one important part of the global population: Our youth."
In his 10-minute speech, Abd Allah said extremism was one of the problems confronting the international community.
He said people worldwide "know it is profoundly anti-peace, anti-progress and antidemocratic." But, he added, "we need to do more, on all sides, to reinforce the basic values of humanity."
Recommendations from the meeting will be presented to political and business leaders meeting Friday at the World Economic Forum on the banks of the Dead Sea in Jordan.
The three-day meeting will discuss social and political reforms in the Middle East, Arab-Israeli peacemaking and Iraq reconstruction.