Atovulloev was detained on August 20 upon arrving at Tbilisi's airport.
Atovulloev told RFE/RL by telephone on August 21 that he was released several hours after his detention and is currently back in Germany, where he has political asylum.
Atovulloev said that, after he arrived in Georgia from the Czech Republic, he was told that he was wanted by Tajik authorities, who accuse him of extremism and terrorism.
The Paris-based international media rights group, Reporters Without Borders, urged Georgian authorities to immediately release Atovulloev, calling the request by Tajik authorities politically motivated.
Atovulloev is well-known for his reports that are critical of Tajik President Emomali Rahmon and members of his family.
Last month, he was denied entry at Moscow's Sheremetyevo airport, where he also arrived from Prague.