At least 15,000 civilians have been killed and 30,000 injured in Iraq since January 2014, a UN report said on Monday.
"Widespread human rights violations and massive displacement continue unabated throughout the country," the report said.
The UN said it recorded at least 44,136 civilian casualties (14,947 killed and 29,189 wounded) as a result of "non-international armed conflict in Iraq."
The report said the figure "only accounts for casualties it was able to verify and acknowledges the real toll may be much higher."
The figure runs up between January 2014 and the end of April 2015, the report added.
More than 3 million Iraqis have been displaced within the country since ISIS seized large swaths of Iraq, including the second largest city, Mosul, after June 2014.
Iraqi refugees face tough challenges and struggle to survive, lacking adequate food aid.
UN’s refugee agency said in June the number of people displaced worldwide by war in 2014 was “larger than in any year.”
Iraq is seeking to restore security across the country as security forces fight against ISIS but the militant group has stepped up its attacks.
A series of car bombs has hit the Baghdad in recent weeks, claiming more than 100 lives.