Chinese Vice Premier Zhang Gaoli and leaders of ASEAN member countries attended the opening ceremony.
With the theme of "jointly building the 21st Century Maritime Silk Road", the expo hosted 4,600 exhibitors, 1,259 of which are from ASEAN countries.
Initiated in 2004, the expo serves as an important platform to promote bilateral trade and relationships between China and the ASEAN.
China is the ASEAN's largest trading partner, while ASEAN ranks as China's third-largest trading partner. The bilateral trade between China and the ASEAN increased 10.9 percent year on year to 443.61 billion U.S. dollars in 2013, around 5.7 times that of 2003.
The ongoing expo is scheduled to run from Sept. 16 to 19.