The liftoff of the vehicle carrying seven spacecraft took place at the site located in the Yellow Sea at 12:06 p.m. local time (04:06 GMT), the China Central Television broadcaster reported.
READ MORE: Air-Launched Ballistic Missile Will Give China Complete Nuclear Triad — Pentagon
The carrier rocket's maiden flight took place in 2015, and a total of six launches have been carried so far, without taking into account Wednesday's flight.
China is not the first country to use an offshore platform for a space launch. A total of 36 launches of the Russian-Ukrainian Zenit-3SL rockets were carried out from the Odyssey platform in the Pacific Ocean in 1999-2014. Prior to that, the United States used the Italian San Marco platform in the Indian Ocean for the launches of its Scout rockets.