The ambitious project is hoping to reveal details about the origins of life on Earth and perhaps elsewhere in the solar system.
The launch comes as the United States space agency celebrates another milestone anniversary.
An elated Ellan Stofan, NASA's chief scientist, spoke after the successful launch of Osiris-Rex as it blasted away from Cape Canaveral in Florida.
"We're going to be answering some of the most fundamental questions that NASA really focuses on. How does this planet work? How did this planet form? And we're even going to be looking at questions as basic as where did life, and how did life, originate on this planet?"
It's the beginning of a seven-year journey for the probe.
It will reach the 4.5 billion year-old asteroid in 2018, before taking a year to study and collect samples which will then be brought back to Earth in 2023.
NASA scientist Lucy McFadden says they'll be looking into the past for the early building blocks of life.
"We're going to Bennu because it's a carbon-rich asteroid, and the carbon minerals are necessary for life to begin. So we're going to Bennu to explore the origins of life as we know it here on Earth, by looking for clues that have been covered up here on Earth but looking to see what the precursors were and how life evolved here on Earth."
But as the space agency turns science fiction into science fact, another milestone is being observed by NASA: the 50th anniversary of the fictional US TV series 'Star Trek'.
In 1966 the USS Enterprise was launched, with its intrepid crew led by Captain James T Kirk, into the vastness of the universe.
Since then there have been countless television series and films.
NASA even named one of its space shuttles after the Enterprise.
In honour of the anniversary, and of the space agency's commitment to diversity, NASA interviewed for its website two stars from the original, talking about the importance of increasing diversity in its space programs.
Nichelle Nichols played Lieutenant Uhura and George Takei was famous for his portrayal of the character Hikaru Sulu.
Mr Takei later told the BBC Star Trek looked to the future with optimism, and that resonated with the audience at a critical time.
"I'm Asian American, Uhura represented Africa, played by an African-American. We heard the diversity as well in the various accents. Scotty spoke with a very heavy Scottish brogue. Chekov spoke with a very heavy Russian accent. And this at a time when the Cold War was at its coldest point, and none of that was being reflected on national television except on Star Trek."
