It is the third unsuccessful launch attempt for the Falcon 1 rocket, built by private space firm SpaceX.
The vehicle's two stages failed to separate two minutes and 20 seconds into launch from Kwajalein Atoll in the Pacific Ocean.
SpaceX's engineers are still investigating the cause of the rocket's failure.
"It was obviously a big disappointment not to reach orbit on this Flight 3 of the Falcon 1," said Elon Musk, chief executive of SpaceX, in a short statement read to reporters.
"The most important message I'd like to send right now is that SpaceX will not skip a beat in execution going forward. We have flight four of Falcon 1 almost ready for flight and flight five right behind that." More...
And this: Cities at night... view from Space. Wow!