Thousands of foreigners have fought on behalf of Islamic State in Iraq and Syria since at least 2014.
The women, said to be aged between 20 and 50, appeared dressed in black at the central criminal court in Baghdad on Sunday.
"But keeping women and children who did nothing wrong beyond having a relative join ISIS out of work, out of school, and in fear of arrest every day will do nothing to foster reconciliation in Iraq".
Human Rights Watch has argued that the sentences are "unfair", with some activists arguing that numerous women were tricked or coerced into joining the terrorist groups.
Iraq has handed over to Russian Federation four women and 27 children suspected of having ties to the group, the foreign ministry said on Thursday, adding that they were "tricked" into joining the militants.
Several women who surrendered to Iraqi forces alongside defeated ISIS fighters have already been sentenced to death or life in prison, according to Human Rights Watch.
About 1,700 women and children linked to an "Islamic state" surrendered or were captured in Iraq.
The Iraqi court said the death sentence of the 16 Turkish women can be appealed.
Just last month, a German citizen was sentenced to death in Iraq for providing Daesh with logistics aid.
A court in Iraq has sentenced more than a dozen Turkish women to death over membership in the ISIS Takfiri terrorist group and involvement in acts of terror across the conflict-ridden Arab country.
Human Rights Watch has raised concerns about the judicial process and branded the trials unfair. It also argues that in cases where a suspect is claimed to be a Daesh member "without evidence of any other serious crime, authorities should consider alternatives to criminal prosecution".