The complex, in the southern Turkish town of Reyhanli near Syria, will house 990 children in 55 homes established by the Humanitarian Relief Foundation (IHH), a Turkish NGO, and Qatar's Foundation Sheikh Thani Ibn Abdullah for Humanitarian Services.
The project, which was begun in July 2015 with the help of the Turkish government, has three schools, a mosque, a health clinic, playgrounds and a cultural centre, the IHH said in a statement.
The IHH said it was the "biggest space dedicated for orphan victims of war in the world", which will also have a special rehabilitation centre for children who have experienced "great traumas".
According to Unicef, 2.3 million Syrian children are living as refugees in Turkey, Lebanon, Jordan, Egypt, and Iraq.
About 1.3 million children and teenagers aged 18 and under are among the 2.9 million registered Syrian refugees living in Turkey, according to the interior ministry.