In a Xinhua video, two J-20s screamed over the huge crowds at Airshow China with bomb bay doors open, showing four long-range missiles mounted inside.
Chinese experts told the state newspaper the airshow demonstration, which was part of the celebration of the 69th birthday of the Chinese People's Liberation Air Force, was to show off the aircraft's superiority to US fighter jets.
The six-day 12th China International Aviation and Aerospace Exhibition (Airshow China) concluded in the southern Guangdong province's Zhuhai city on Sunday.
The planes, developed by China's Chengdu Aerospace Corporation for the People's Liberation Army Air Force (PLAAF), represent Beijing's foray into stealth aircraft engineering.
The third stage of the plan provides for the creation of a world-class air force by around the 2050s that would reflect China's status as one of the world's most powerful nations.
With upgraded engines, the J-20 will likely become a much more capable weapon.
First, a strategic force will be established by 2020. For the first time, the aircraft's missile bay was opened to the public, revealing what was reportedly six long-range air-to-air missiles, in addition to two mounted short-range combat missiles.
Deals worth more than 21.2 billion US dollars have been signed at the 12th China International Aviation and Aerospace Exhibition (Airshow China).
China displayed a host of its latest tactical weapons including a new intelligence radar, anti-ship missile as well as an unmanned missile boat at the air show. A total of 770 firms, including Boeing and Airbus, from 43 countries and regions participated in the event. "The scale of the exhibition has reached a new high, improving not only in quantity but also quality".