Police said they had “successfully secured the release” of the men on Friday and that no ransom was paid to the kidnappers.
Spokesman Frank Mba told AFP on Sunday that the four were in “good health.”
“We have three suspects in custody and recovered one AK-47 rifle. We are now intensifying our search for others involved,” Mba said.
The gunmen snatched the four men after storming a bar in a village in the western Kwara state last Saturday.
Local media said the Turks were working for a construction firm in the state.
Kidnapping for ransom is common in Nigeria, especially in the oil-rich south and the northwest.
Gangs have often targeted foreign workers, and victims are usually released after a ransom is paid.
Ten Turkish sailors were kidnapped by armed men from a cargo ship off the Nigerian coast earlier this month.
The Nigerian navy has said it is searching for the men in the Niger delta area.