In 2004, the industry's annual sales totaled 100 billion yuan, with 870,000 practitioners in 100,000 business units. Today, the number of practitioners and business units have surged to 2.6 million and 445,000, said Gan.

The fast-developing industry has become the world's second-largest ad market, after the United States.

The congress hopes to attract more foreign advertisers as well as encouraging local advertising firms to keep an eye on the global market, said Gan.

The industry not only plays a role as a service industry but is also an economic barometer, Gan said.

The industry's annual revenue as proportion of GDP stayed at a relatively low level, 0.91 percent, in 2012 and later stagnated in 2013 to 0.88 percent.

"The share in developed countries is normally over 2 percent, but we are still far behind," said Gan. "Thus, while our industry is not a great powerhouse yet, we will win in sales quantity."

Meanwhile, experts warned that changing the existing sales model is vital.

"Fewer people will run advertisements through agencies in the future," said Chen Xianhong, a professor of advertising at Huazhong University of Science and Technology. "It's the market trend."