An ally of Western-leaning President Mikheil Saakashvili in the 2003 "rose revolution", Okruashvili, 33, known for his strong-worded remarks about Russia, was appointed economics minister on November 10 in a reshuffle seen by analysts as a move to defuse an acute diplomatic crisis with Moscow.
"Irakly Okruashvili... has submitted his resignation to Prime Minister Zurab Nogaideli," the ministry's spokeswoman Nana Intskirveli said, adding the government would now have to approve the resignation.
The spokeswoman did not specify the reasons for the minister's decision.
As a Defense Ministry "hawk", Okruashvili often made harsh statements causing outrage in Moscow. He promised to celebrate New Year in the breakaway pro-Russian republic of South Ossetia, and said Russia was doomed to defeat in any potential warfare with Georgia.
Petre Mamradze, who heads the government chancellery, said the staff of the prime minister or the government had not received official resignation announcement from the minister.
"We have received no written resignation statement," Mamradze said.
The economics ministry's press service said Okruashvili was currently outside Georgia.
Many saw the appointment as economics minister of Okruashvili - who wielded considerable power in domestic and foreign affairs - as a demotion. In the past, Okruashvili had held the posts of deputy justice minister, prosecutor general, and interior minister.
