At least 10 rockets landed on Wednesday at Iraq's Ain al-Asad airbase that hosts U.S., coalition and Iraqi forces, the Iraqi military said.
It was the second rocket attack in Iraq this month and came two days before Pope Francis is due to visit the country. The Pope will visit Iraq from March 5-8 despite deteriorating security in some parts of the country.
The attack caused no significant losses, Iraq's military said without going into further detail.
A Baghdad Operations Command official said earlier that about 13 rockets were launched from a location about 8 km (5 miles) from the base, which is in western Anbar province.
Another Iraqi security source and a government official who spoke on condition of anonymity said the rockets were launched from the Baiader area, west of Baghdadi city.
On Feb. 16 a rocket attack on U.S.-led forces in northern Iraq killed a civilian contractor and injured a U.S. service member.
U.S. Army Colonel Wayne Marotto, spokesman for the U.S.-led coalition, said on Twitter that the rockets targeted the base at 7:30am Iraq time on Wednesday.
The Pentagon said Monday that a retaliatory U.S. airstrike last week in eastern Syria killed one fighter in an Iranian-backed militia and wounded two others.
"What I can tell you is that we believe right now there was likely one militia member killed, and two militia members wounded," Pentagon press secretary John Kirby told reporters.