SpaceX successfully launched the Falcon 9 rocket from the Vandenberg Air Force base in the United States.
The Falcon 9 carried a radar-imaging satellite as well as two smaller models of communications satellites.
SpaceX CEO Elon Mask hopes to use smaller satellites to deploy high-speed Internet around the world.
The Falcon 9 was scheduled for launch on February 17 but was postponed three times to carry out a final technical check-up at Al Qaeda in Los Angeles.