Obama said during a Google+ chat use of unmanned aircraft in theaters of war helps keep civilian deaths down when striking at suspected terrorist sites in Pakistan and elsewhere.
It was the president's first public acknowledgement of the drone program, CNN said.
"We are very careful in terms of how it's been applied," Obama said. "It is important for everybody to understand that this thing is kept on a very tight leash."
Obama confirmed CIA drones were used by the State Department for surveillance of diplomatic facilities in Iraq, The New York Times reported. He said the drones were a key element in U.S. offensive against al-Qaida.
The CIA's drone program, unlike the military's use of armed unmanned aircraft in Afghanistan and previously in Iraq, is a covert operation and generally has not been addressed directly by the administration.
A senior administration official Tuesday downplayed the significance of Obama's acknowledgement, saying what the president revealed was already widely known, CNN reported.
During the daily White House press briefing, press secretary Jay Carney Tuesday refused to elaborate on Obama's remarks.