This is also an important moment spotlighting China's leadership, as the summit is expected to see consensus and coordinated measures to tackle challenges facing both developed and developing countries.
"We have high hopes for China's leadership at G20," says John Kirton, co-director of G20 Research Group at the University of Toronto, Canada.
This is not only because China is the world's largest economy and an important powerhouse of global growth.
"At the same time, the role that China can play in bringing together developing and developed countries is very important," says Ramon Pacheco Pardo, a senior lecturer on international relations at King's College London.
In Kirton's opinion, China's leadership also lies partly in "its recurrent strong wisdom to adjust to the overwhelming consensus and the consensus of its partners to produce collective success."
Such an openness and broad vision have helped China in preparing the the G20 summit for a success. Among its efforts is initiating the G20 trade and investment working group and making regular the meeting of G20 trade ministers.
The trade ministers agreed in Shanghai last month to lower trade cost, harness trade and investment policy coherence and enhance trade in services as part of coordinated efforts to boost global trade growth, which is top on the summit's agenda set by China.
The ministers said in a joint statement that trade and investment should continue to be important engines of global economic growth and development.
"I think there're strong protectionist pressures in the world," says Robert Kahn, a senior fellow on international economics at the United States Council on Foreign Relations. "Here's what China can play a very important role in showing the leadership, saying we need to resist these pressures and we need to do it in a way that's realistic and smart."
While addressing the concern of developed countries over a lack of growth impetus, a blueprint for innovation-driven growth that China will put forward at the Hangzhou summit is also expected to benefit developing countries in that innovation also means the spread of existing technologies.
Under China's presidency, the G20 summit is also expected to seek a stronger say for developing countries in reforming global economic and financial mechanisms and launch an initiative to support the industrialization in Africa and the least developed countries.
An action plan to carry out the United Nations 2030 Agenda for Sustainable Development is also what China has committed itself to the summit, which will put development at the top of the macro-policy agenda for the first time in G20 history.
China's leadership is helpful given its desire for consensus-based work. "It's quite visible. It is better suited to governance for the 21st century," Kirton says.
Tristram Sainsbury, a researcher at the Sydney-based Lowy Institute for International Policy, hails China's presidency of this year's G20 summit as among the "most highly anticipated" for the G20, which is regarded as a top multilateral economic governance forum.
In his eyes, China can be both ambitious and realistic, while focusing on a few practical goals. "The hope is that China can leave a positive legacy that reverberates for years to come."