Beijing has poured billions into such ambitious projects as well as its military-backed space programme, including the launch of its second space station earlier this month.
Measuring 500 meters (1,640ft) in diameter, the radio telescope is nestled within a stunning landscape of lush green karst formations in southern Guizhou province.
The facility took five years and around £140 million to complete, and surpasses the capability of the 300-metre (985ft) Arecibo Observatory in Puerto Rico, a dish used in research on stars which led to a Nobel Prize.
China’s official Xinhua News Agency said hundreds of astronomers and enthusiasts watched the launch of the Five-hundred-metre Aperture Spherical Telescope, or FAST.
Researchers said FAST would search for gravitational waves, detect radio emissions from stars and galaxies and listen for signs of intelligent extraterrestrial life.
“The ultimate goal of FAST is to discover the laws of the development of the universe,” said Qian Lei, an associate researcher with the National Astronomical Observatories of the Chinese Academy of Sciences.
“In theory, if there is civilisation in outer space, the radio signal it sends will be similar to the signal we can receive when a pulsar (spinning neutron star) is approaching us.”
Earlier this month, China launched the Tiangong 2, its second space station and the latest step in its military-backed programme which intends to send a mission to Mars in the coming years.
In August, the country launched the first quantum satellite, which experts said would advance efforts to develop the ability to send communications that cannot be penetrated by hackers.
CCTV reported that during a recent test, the telescope received radio signals from a pulsar that was 1,351 light-years from Earth.
The radio telescope has double the sensitivity of the Arecibo Observatory, and five to ten times the surveying speed.
China has also completed the construction of tourist facilities such as an observation deck on a nearby mountain.
Such facilities can be a draw for visitors – the one in Puerto Rico draws about 90,000 visitors and some 200 scientists each year.