Greek authorities say the 202 migrants and refugees who had not applied for asylum in Greece and were returned to Turkey included people from Pakistan, Afghanistan, Iraq and Congo.
The Greek civil protection ministry said 136 people - 135 men and one woman - were returned from the island of Lesbos.
They included 124 people from Pakistan, three from Bangladesh, one from Iraq, two from India, four from Sri Lanka and two Syrians.
The Syrians had asked to be sent back themselves, the ministry said.
Another 66 - 56 men and 10 women - were returned from the nearby island of Chios, including 42 Afghans, 10 Iranians, six Pakistanis, five people from Congo and one person each from India, Somalia and Ivory Coast.
Meanwhile, Turkish Prime Minister Ahmet Davutoglu has called on police officers to show compassion as his country received the first Syrians turned back from Greece.
Speaking at the 171st anniversary ceremony of the founding of the Turkish police force, Mr Davutoglu urged police officers not to "distinguish them from our own citizens".