While it is known that the next president and premier will be Xi Jinping and Li Kepiang, other details will not be revealed until the Congress ends.
On Thursday, China's outgoing President Hu Jintao used his opening speech to praise his country's performance despite a slowdown in economic growth.
However, he said a new Chinese growth model, marked by greater domestic demand and private enterprise, was essential to ensure the long-term health of China's economy.
"In response to changes in both domestic and international economic developments, we should speed up the creation of a new growth model and ensure that development is based on improved quality and performance," he said.
The president also said his country still has much to do, fixing corruption and environmental problems.
Watch China correspondent Stephen McDonell's preview of the Chinese congress here.
As the Congress opened, there were reports that at least four Tibetans had set themselves on fire in a protest against Beijing's rule in Tibet.
The Tibetan government-in-exile confirmed four incidents had taken place on the eve of the gathering, while Radio Free Asia reported a fifth.
They said that two of the five people had died from their injuries.
Here is how the process works and some pointers on what is at stake:
Over the next week, the 2,270 delegates will appoint about 370 members of the party's elite Central Committee.
The Committee's first session, held the day after the Congress ends, will then select around two dozen members of the decision-making Politburo.
The new Politburo Standing Committee, the party's top echelon of power which currently has nine members, will then be unveiled after the one-day Central Committee meeting ends.
The new president will be Xi Jinping, Li Kepiang will be the next premier, but who will fill the remaining five positions on the Politbureau Standing Committee is still a secret.
Vice-president Xi Jinping is set to take over as party general secretary from president Hu Jintao at the end of the Congress.
He will then take over as head of state in March, at the annual full meeting of parliament.
It's uncertain whether Hu Jintao will also give up his job as military chief. His predecessor, Jiang Zemin, stayed on in that role for two years after stepping down as party chief.
A total of 2,270 delegates have been selected to attend this year's congress. About one-third have been picked by regional officials as "grassroots" role models from all walks of life, including farmers, workers, teachers, doctors and scientists.
Celebrity delegates include Mao Zedong's grandson, Mao Xinyu.
The Communist Party has more than 82 million members.
How long will it last?
The Congress is expected to last one week.
The delegates are meeting in Beijing's cavernous Great Hall of the People for full sessions.
But most of the real business will take place behind closed doors at the Jingxi Hotel in western Beijing.