The epicentre of the quake on Sunday was 32 km southwest of the Halabja area near the Iranian border at the depth of 33.9 km, according to the US Geological Survey (USGS), Xinhua news agency reported.
Earlier reports suggested that the quake's magnitude stood at 7.5.
The state-controlled television said at least eight villages were damaged. The centre was reported by the USGS to be in the southeast of Iraq's Sulaymaniya province, close to the Iranian border.
Residents of the northern Iraqi city of Erbil in the street after the quake hit.
No casualties have yet to be reported.
Many residents in the Iraqi capital of Baghdad and also in other cities including Irbil in the Kurdistan region rushed out of houses and buildings in panic.
Majida Ameer, who ran out of her building in the capital's Salihiya district with her three children, said: 'I was sitting with my kids having dinner and suddenly the building was just dancing in the air. But then I heard everyone around me screaming "Earthquake!"'.
The natural disaster was felt in many Iraqi provinces in the north and central regions, including the Iraqi capital Baghdad, witnesses said. The University of Tehran has reported at least four aftershocks, the biggest of which was magnitude-4.6.
Iran is prone to near daily quakes as it sits on many major fault lines.