The court in the eastern city of Mus ruled that the man, identified as Ertan P, insulted Islamic values with his Twitter handle -- @allah (cc) -- and a series of tweets he posted, Hurriyet newspaper reported on its website.
The defendant claimed his account had been hacked and appealed against the sentence, Hurriyet said.
Pretending to tweet as God, he wrote: "In my present state of mind, I would not have created the little finger of human beings".
The Islamic-rooted government banned Twitter in March after the micro-blogging site was used to spread corruption allegations against Prime Minister Recep Tayyip Erdogan and his inner circle.
The ban, which earned Turkey a strong rebuke from rights groups and its Western allies, was lifted two weeks later after the country's top court ruled that it violated rights.
Citing the same reason, the Constitutional Court today lifted a similar ban on Youtube, also imposed in March after the website was used to spread damaging leaked audio files from a state security meeting debating possible military action in Syria.