They say the workers were employed by a Turkish construction company, Nurol Insaat, contracted to build a sports complex in the predominantly Shia northeastern Baghdad district of Habibiyah.
Officials said that armed men wearing military uniforms stormed the construction site around 8am local time on Wednesday and took them away in several black pick-up vehicles.
The kidnappers stormed the construction site, where the workers were sleeping in caravans, breaking down doors and disarming the guards before taking the workers away.
Turkish Deputy Prime Minister Numan Kurtulmus has told news agencies he is in contact with Iraqi authorities over the incident.
"The Iraqi authorities for the time being do not have information on how the incident occurred or who captured them," he told reporters.
A spokesperson for Turkey's foreign minister, Tanju Bilgic, told the AP news agency that the Turkish nationals taken included workers, engineers and an accountant.
He said the Turks were specifically targeted as they were picked out from the rest, while workers from other countries were left behind.
Last year, 46 Turkish citizens were seized by Islamic State of Iraq and the Levant (ISIL) fighters in Mosul, but were released unharmed after more than three months in captivity.
Source: Bloom Gist and Agencies
