Among the most notable absentees were Hosni Mubarak of Egypt, the most populous Arab country, and King Abdullah of Saudi Arabia, the richest member.
Some of the absent leaders cited security concerns while others have political differences with the Sudanese government.
The US had also asked friendly Arab leaders to stay away to prevent a show of support for the Sudanese government, which is under international pressure to allow UN peacekeepers in the war torn western region of Darfur, several Arab diplomats said.
Diplomats also said the summit was likely to be shortened to one day instead of two, due to the number of absences.
The Arab leaders are expected to discuss financial support for the Palestinian Authority (PA) after a Hamas government takes office, Arab attempts to reconcile Iraqi political factions, and the Darfur conflict.
The Arab ministers, in draft resolutions that the heads of state are expected to endorse, criticised Israel's stated intention of unilaterally fixing its borders, and called on the international community to continue Palestinian aid programmes and to "respect the democratic choice of the Palestinian people".
The foreign ministers also pledged to maintain Arab assistance to the PA at $55 million a month, with the option of an increase.
But the outgoing Palestinian cabinet has said the PA will need a minimum of $130 million if the EU and other donors cut off funds in protest against Hamas's refusal to recognise Israel.
Also on the agenda is the renewal of Amr Moussa's term as secretary-general of the Arab League.
The leading Sudanese daily Al-Sahafa reported that Yemen was putting forward its own candidate at the last minute.
Leaders are expected to push for a stronger Arab role in shaping the future of Iraq to counter growing Iranian influence there, and to support further Arab League efforts at reconciling the various Iraqi factions.
The league's foreign ministers have recommended that their governments forgive Iraq billions of dollars in debts.
The draft also urges Iraqis to form a national unity government that would clear the way for the withdrawal of US-led forces.
Sudan seeking support
Sudan is hoping to use the summit to garner the support of other Arab countries in its position on the Darfur conflict, where it is resisting Western pressure to replace the African Union peacekeeping force with a much bigger UN force.
While the draft resolution on the table offers only vague support for Sudan, it stipulates that Khartoum must approve any deployment on UN peacekeepers to replace a cash-strapped African Union force.
A Sudanese request for money to support the 7,000-strong force was unfulfilled.
More than 180,000 people have been killed in three years of fighting in Darfur, in western Sudan, and more than 2 million people have been displaced.
The African Union recently extended its peacekeeping mandate there until September 30.
Sudan is eager to avoid UN intervention in Darfur, and says the African force can do the job as long as it receives money to overcome its financial and logistical problems.