"The claim that July 2010 was the deadliest month in Iraq since May 2008 is incorrect," the statement said.
The statement did not say how the US military calculated its death toll.
Casualty counts are difficult to tally in Iraq, for a variety of reasons. Ministries do not always keep accurate tallies, and the number of fatalities is often adjusted several times, particularly following major attacks.
Al Jazeera reports for the month showed at least 362 fatalities occured. Another set of data, provided by a security consulting firm AKE, showed roughly 300 people killed in July.
Weekly data from AKE shows an increase in violence over the last four weeks
Regardless of the exact number of deaths, violence has apparently increased in Iraq.
On average about 50 Iraqis have been killed each week in 2010, according to the security firm's data.
In July, though, the death toll stayed at or above that level for four weeks - the only time this year Iraq has seen such a sustained "above-average" level of violence.
July also saw an unusually high number of mass-casualty attacks. Seventy people were killed in the three-day period leading up to a Shia pilgrimage in Baghdad on July 8. A suicide bomber also killed more than 45 people west of Baghdad on July 18.
And two car bomb attacks in late July, in Baquba and Karbala, killed 30 and 21 people respectively.
US officials have sought to stress Iraq's improved security as they prepare to withdraw tens of thousands of troops next month.
Lanza called the continued violence "sporadic" and "not unexpected" [EPA]
General Stephen Lanza, the spokesman for the US military in Iraq, e-mailed reporters in July and urged them to provide "context" in reporting on the Iraqi insurgency.
"I believe it's important to take a holistic view of security in Iraq," Lanza said in his e-mail.
"Overall, the security situation in Iraq is stable ... yes, there are violent acts; but certainly, current trends cannot be accurately characterised as a rise or surge in violence."
Violence in Iraq has dipped markedly from its peak in 2006 and 2007, when dozens of people were killed each day.
But anti-government fighters do continue to carry out attacks on a daily basis, taking advantage of a political vaccum left when March elections left no clear winner.
Iraqi political parties, meanwhile, continue to wrangle over who will lead the next government.