The 18th CPC Central Committee will in turn elect the political bureau, the standing committee of the political bureau and the general secretary at its first plenary session on Thursday.
Xi, who is expected to be elected as the new general secretary of the CPC and China's president, and Li, set to be the next Chinese premier, were elected into the 18th Central Committee of the Communist Party of China at the closing session of the party's 18th National Congress in Beijing at the Great Hall of the People.
Xi is also expected to take over from Hu Jintao as China's president in March 2013.
Xi, 59, is member of the standing committee of the Politburo of the 17th CPC Central Committee, vice president and vice chairman of the CPC Central Military Commission.
Li, 57, is also member of the standing committee of the political bureau of the 17th CPC Central Committee and vice premier.
Both the leaders are likely to get an extension after the end of their first five-year term. China's leadership change happens every 10 years.
State-run Xinhua news agency reported that other top members of the Central Committee were: Wang Qishan, Liu Yunshan, Liu Yandong, Li Yuanchao, Wang Yang, Zhang Gaoli, Zhang Dejiang and Yu Zhengsheng.
The party Congress opened on 8 November with a work report from Hu. Since then, the decision-making has been taking place behind closed doors -- with many of the key selections in reality decided in advance.
Image: Xi Jinping and Li Keqiang attend 18th Communist Party Congress in Beijing | Photograph: Feng Li/Getty Images