If the return journey is successful, China will be only the third country to have retrieved samples from the Moon, following the US and Soviet Union in the 1960s and 1970s.
A Chinese lunar probe has lifted off from the Moon with a cargo of lunar samples on the first stage of its return to Earth, state media reported.
Chang'e 5, the third Chinese spacecraft to land on the Moon and the first to take off from it again, is the latest in a series of increasingly ambitious missions for Beijing's space programme, which also has a spacecraft en route to Mars carrying a robot rover.
The spacecraft touched down on the Moon on Tuesday on a mission to bring lunar rocks back to Earth for the first time since a Russian spacecraft did so in 1976.
Its ascender module lifted off from the lunar surface shortly after 1500 GMT and was to connect with its return vehicle in lunar orbit and transfer the samples to the capsule.
Search for minerals, water content
Chang'e 5's lander module, which remained on the Moon, is equipped to both scoop samples from the surface and drill 2 metres to retrieve materials that could provide clues to the history of the Moon.
While retrieving samples was its main task, the lander is also equipped to extensively photograph the area surrounding its landing site, map conditions below the surface with ground penetrating radar, and analyse the lunar soil for minerals and water content.
Landing in Inner Mongolia
Chang'e 5's return module is supposed to touch down on the grasslands of Inner Mongolia, where China's crewed Shenzhou spacecraft have made their returns since China first put a man in space in 2003, becoming only the third country do so after Russia and the United States.
Chang'e 5 has revived talk of China one day sending a crewed mission to the moon and possibly building a scientific base there, although no timeline has been proposed for such projects.
China also launched Its first temporary orbiting laboratory in 2011 and a second in 2016. Plans call for a permanent space station after 2022, possibly to be serviced by a reusable space plane.
While China is boosting cooperation with the European Space Agency and others, interactions with NASA are severely limited by US concerns over the secretive nature and close military links of the Chinese programme.