Iraqi High Tribunal spokesman Mohammed Abdul-Sahib did not say when Aziz, 74, would be put to death.
Aziz has 30 days to launch an appeal. If the Appeals' Court upholds the death sentence, the law says Aziz should be hung within 30 days of the final decision. The Iraqi president also needs to sign off on an execution order.
Aziz, a Christian who became the international face of Saddam's regime, was in court on Tuesday. He was wearing a blue suit and sat alone, bowing his head and frequently grasping the handrail in front of him, as the judge read out the verdict.
It was not immediately clear if Aziz's Jordan-based lawyer, Badee Izzat Aref, will appeal the verdict, which he called politically motivated.
"We are discussing this issue and what next step we should take," Aref told The Associated Press in Amman, the Jordanian capital.
Aziz has already been convicted and sentenced to 15 years in prison for his role in the 1992 execution of 42 merchants found guilty of profiteering. He also received a seven-year prison sentence for a case involving the forced displacement of Kurds in northern Iraq.
Aref questioned the timing of the death sentence, accusing al-Maliki's Shiite-led government of trying to divert attention from recent WikiLeaks revelations of prisoners' abuse by Iraqi security forces and the U.S. military.
