The plane had just lifted off from the Sulaimaniyah airport around 5 p.m. when the fire broke out in one of its engines, officials said. It tried to land but crashed in a heavy snowstorm.
Airport head Tahir Abdullah Qadir said the private twin-engine plane carried four foreign businessmen working for AsiaCell, one of Iraq's largest mobile phone companies. He would not say what nationality the passengers were but said the plane was headed to the Turkish capital of Ankara.
Three crew members aboard also died, Qadir said.
Qadir said the initial investigation indicated the fire was the result of a mechanical problem and was not linked to the bad weather.
Firefighters battled the flames for more than two hours before extinguishing the blaze, officials said. Ambulances could be seen speeding into the airport complex, but journalists were barred from entering the area.
Sulaimaniyah is 160 miles (260 kilometers) northeast of Baghdad.