The air defence system at the Ain al-Assad base, located in western Iraq, intercepted and shot down the two drones, the Iraqi military-linked Security Media Cell said.
No casualties or damage was reported, reports dpa news agency.
The attempted attack was the latest in a series against the same base.
Last month, an air attack targeted Ain al-Assad, causing no casualties.
In March, a US civilian contractor died in a rocket attack on the facility.
Ain al-Assad was one of the bases that Iran attacked in January 2020 to avenge the killing of top Iranian general Qasem Soleimani in US strikes on Baghdad.
In recent months, the heavily fortified Green Zone in Baghdad, home to the US embassy, and facilities hosting US troops in Iraq have been the target of repeated attacks blamed on pro-Iranian groups.