Osman Kavala was detained at Istanbul’s Ataturk airport after flying in from the southern city of Gaziantep, the Dogan news agency said.
Kavala is the chairman of the Anadolu Kultur (Anatolian Culture) NGO which aims to overcome differences within Turkish society especially through culture and the arts.
The organization has also sought to reach out to Armenia, with whom Turkey has no relations partly due to the dispute over the mass killings of Armenians under the Ottoman Empire which Yerevan regards as genocide.
Dogan news agency said Kavala had been in Gaziantep to discuss a project with Germany’s cultural outreach organization the Goethe Institut.
It said he was detained in line with an investigation by Istanbul prosecutors, without giving further details.
The arrest comes as concern intensifies over the fate of Turkish civil society under the state of emergency imposed after last year’s failed coup that aimed to oust Erdogan.
Eleven human rights activists, including the two top figures from Amnesty International’s Turkey branch, will go on trial in Istanbul next week on hugely-controversial terror charges.
Meanwhile, 156 journalists, most detained under the state of emergency, are currently behind bars, according to the P24 activist group.
Amnesty’s Turkey researcher Andrew Gardner said on Twitter the arrest of Kavala was the “latest attack on civil society in Turkey.”
“Osman Kavala has worked tirelessly to build reconciliation, dialogue and support the rule of law in Turkey,” added Emma Sinclair-Webb of Human Rights Watch.
Reports said Kavala was born in Paris but took over the family business when his father died. He is also the co-founder of the Iletisim publishing house.