China has entered a new era where it should take centre stage in the world, President Xi Jinping says. The country's rapid progress under socialism with Chinese characteristics shows there is a new choice for other countries, he told the Communist Party congress.
The closed-door summit determines who rules China and the country's direction for the next term. Xi has been consolidating power and is expected to remain as party chief.
The congress, which takes place once every five years, will finish on Tuesday. More than 2,000 delegates are attending the event, which is taking place under tight security.
Shortly after the congress ends, the party is expected to unveil the new members of China's top decision-making body, the Politburo Standing Committee, who will steer the country.
Listing China's recent achievements in his three-hour speech, Mr Xi said that socialism with Chinese characteristics in this new era meant China had now become a great power in the world, and had played an important role in the history of humankind.
The Chinese model of growth under Communist rule was flourishing, he said, and had given a new choice to other developing countries. It is time for us to take centre stage in the world and to make a greater contribution to humankind, he added.
Since Xi took power in 2012, China's economy has continued to grow rapidly. But correspondents say the country has also become more authoritarian, with increasing censorship and arrests of lawyers and activists.
In his speech Xi also described a two-stage plan for China's socialist modernization by 2050, which would see it become more prosperous and beautiful through environmental and economic reforms.
He warned against separatism - in an apparent reference to movements in Xinjiang, Tibet and Hong Kong - and reiterated the government's principle that Taiwan is part of China and added China would not close its doors to the world and promised to lower barriers for foreign investors.
He also introduced measures to increase party discipline, and touched on his wide-reaching corruption crackdown that has punished more than a million officials.
An austerity drive, instituted by Mr Xi, has meant a more pared down congress, with reports this week of delegates' hotels cutting back on frills such as decorations, free fruit in rooms and lavish meals.
Meanwhile, state media have said the Party is expected to rewrite its constitution to include Mr Xi's work report or political thoughts, which would elevate him to the status of previous Party giants Mao Zedong and Deng Xiaoping.