An Istanbul court freed the defendants under a new law passed in March reducing the detention limit for suspects on trial from 10 years to five years, the Turkish Journalists' Union said on Thursday.
Among those affected by the court ruling is Fusun Erdogan, who holds dual Turkish and Dutch citizenship and is director of Ozgur Radio, which broadcasts in Kurdish.
Erdogan, who was detained in 2006, is appealing her November sentence of life in prison along with the seven others for belonging to the banned Marxist-Leninist Communist Party (MLKP), listed as a terrorist organization by Turkey.
The European Federation of Journalists (EJF) said on Thursday that 32 journalists were still in jail, most of them for suspected links to the banned Kurdistan Workers' Party (PKK).
The release of the three journalists "has given us new hope for our campaign to decriminalize journalism in Turkey but we need to go on for those journalists who are still behind bars in Turkey," said Mogens Blicher Bjerregard, EFJ president.
Turkey has long been criticized for a lack of press freedom.
In December, the US-based Committee to Protect Journalists described Turkey as the world's number one jailer of journalists for the second straight year.
BA/BA