State explosives experts testified that the men were caught with explosives of an "enormous destructive power".
The indictment did not directly link the men to al-Qaeda but Saad Fakhri Yunis al-Nuaimi, one of the Iraqis claimed that another of the plotters told him that the group would claim responsibility for the attack.
The men were also charged with allegedly planning attacks on Israeli and American tourists in hotels on the Dead Sea and in the Red Sea port of Aqaba, as well as illegal possession of explosives.
They were arrested during a raid in March during which security forces alllegedly found explosives of the type used in three co-ordinated suicide bombings on hotels in Amman in 2005.
At least 59 people were killed in the hotel attacks which were claimed by al-Qaeda in Iraq.
The jailed men have 30 days to appeal against their sentences.