Majid served as Saddam Hussein's defence minister
Ali Hassan al-Majid, a former Iraqi official known as Chemical Ali, has been sentenced to death for ordering the gassing of Kurds.
It is the fourth time that Majid, an enforcer in Saddam Hussein's regime, has been sentenced to death.
He has also been convicted of the killings of Shia Muslims in 1991 and 1999 and for his role in a campaign of genocide against Kurds in the 1980s.
His latest sentence is for a gas attack on the Kurdish town of Halabja in 1988.
It is believed that 5,000 people died in the attack, most of them women and children. Iraqi jets swooped over Halabja and for five hours sprayed it with a lethal cocktail of mustard gas and the nerve agents Tabun, Sarin and VX.
Majid was a cousin of Saddam Hussein, and earned his nickname after his use of poison gas.
HALABJA ATTACK 1988
16 March: Kurdish town of Halabja hit by gas attack
Iraqi aircraft drop mustard and nerve gas bombs
About 5,000 people killed, mostly women and children
Part of wider "Anfal" campaign against Kurds
Happened near end of Iran-Iraq War
Survivors cancer-prone, birth defects common
The Al-Iraqiya channel said Majid would be killed by hanging.
The Iraqi High Tribunal also sentenced former defence minister Sultan Hashem to 15 years in prison for the Halabja attack, a court official said, quoted by Reuters.
The BBC's Jim Muir, in Baghdad, says that for Kurds, Halabja is the single most traumatic atrocity they suffered during Saddam Hussein's long campaign against them in the 1980s and they had wanted Majid to face justice for it.
It is believed Iraqi authorities will now want Majid executed without delay.
However, he does have the right of appeal, our correspondent adds.
Majid was captured in August 2003, five months after US forces invaded Iraq.
He was sentenced to hang in June 2007 for his role in a military campaign against ethnic Kurds, codenamed Anfal, that lasted from February to August of 1988.
In December 2008 he also received a death sentence for his role in crushing a Shia revolt after the 1991 Gulf War.
In March 2009 he was sentenced to death, along with others, for the 1999 killings of Shia Muslims in the Sadr City district of Baghdad.
The Iraqi High Tribunal was set up to try former members of Saddam Hussein's mainly Sunni government and was the same one that sentenced the former president to death.