The location of the base was first disclosed by The New York Times online.
A drone flown from there to Yemen was used two years ago in the operation to kill Awlaki, a US-born cleric alleged to be the operations chief of al-Qaeda in the Arabian Peninsula.
US media, including the Associated Press, knew of its existence then, but have only reported on it now.
Any operation by US military or intelligence officials inside Saudi Arabia is politically and religiously sensitive. Al-Qaeda and other militant groups have used the Gulf kingdom's close working relationship with US counterterrorism officials to stir internal dissent against the Saudi regime.
"Rightful liberty is unobstructed action according to our will within limits drawn around us by the equal rights of others. I do not add 'within the limits of the law' because law is often but the tyrant's will, and always so when it violates the rights of the individual." Thomas Jefferson