The man, identified as Musa Goktas from Ankara, illegally crossed into Syria in October with his 15-year-old twin sons to join the jihadist group, the online newspaper Radikal said today.
He was arrested on his way back to Ankara in late January, during a police search of a bus in the southeastern province of Gaziantep, near the border with Syria.
Radikal said Goktas was returning home to sell his house, settle his debts and take his wife with him back to Syria.
"I wanted to live by my faith and wanted to join IS which I felt close to, because of the way they practised our religion," Goktas was quoted as telling a preliminary court hearing in Ankara to decide on his pre-trial detention.
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The 38-year-old suspect reportedly admitted to taking his sons into an area of Syria controlled by Islamic State, which hired the trio as cooks, paying them each a monthly salary of USD90 (79 euros).
Radikal said it was the first time a Turkish citizen had been detained over links to IS.
In a separate development, the Turkish army said on its website that four suspected IS members had been "captured" in the southeast of the country.
There were no immediate further details.
Turkey has long been accused of not doing enough to stem the flow of jihadists seeking to join Islamic State, which has captured large swathes of territory in Syria and Iraq.
According to Foreign Minister Mevlut Cavusoglu, up to 700 Turkish nationals have joined IS.
Ankara says it has stepped up border security and that Western countries also have a responsibility to share intelligence about would-be jihadists who use Turkey as a gateway to Syria.