The Turkish information technology authority BTK has fined social network service Twitter for refusing to remove offensive content from its site, the state-run Anadolu news agency reported on Friday.
Twitter will have to pay 150,000 lira (50,689 dollars), according to the report.
Despite court orders, Twitter had failed to remove content glorifying terrorism among things, the Turkish government said justifying the fine.
The comments are thought to refer to Tweets regarding the banned Kurdistan Workers' Party PKK.
According to Anadolu, it is the first time that the BTK has imposed sanctions on a social media provider.
Turkey called for the removal of content more often than any other country during the first six month of 2015. Some 408 requests were made by the courts, another 310 were made by government departments, as Twitter online statistics show.
Overall, more than 70 per cent of all removal requests worldwide originated in Turkey.
In March 2014 Turkish authorities had blocked Twitter and YouTube following corruption allegations against individuals connected to the ruling AKP party posted online. The constitutional court later lifted the ban.
In an ironic twist, the move against the social media provider comes only a day after President Recep Tayyip Erdogan - on his own Facebook page - paid tribute to Facebook founder Mark Zuckerberg for his solidarity with Muslims.