In addition, 7,400 people have suffered serious injuries, the organization said on Friday.
Other organizations and media outlets are reporting higher death tolls. Over the weekend, the British newspaper The Times, which spoke to several doctors in Iran, reported that at least 16,500 protesters had been killed and well over 300,000 injured during protests against the regime.
It is still difficult to get information from the country, due to the regime's shutdown of the internet and telephone services. For over two weeks, Iran has been almost completely cut off from the outside world.
Iran's ayatollah has previously admitted that "several thousand" have been killed in the protests, but has blamed the deaths on the United States.
Corrected: In an earlier version of the text, there was an incorrect number in the title.
