The party constitution, or charter, is a document of ultimate authority by which all 96 million party members must abide, and amendments remain effective indefinitely.
Xi also amended the constitution in 2017, when he incorporated an ideology with his name - Xi Jinping Thought on Socialism with Chinese Characteristics in the New Era - into the constitution, putting him on par with leaders Mao Zedong and Deng Xiaoping.
Xi, 69, is widely expected to be confirmed on Sunday to a third five-year leadership term as party general secretary.
Saturday's revisions incorporate priorities and policy directions that Xi had outlined in the past, including: "Two Establishes", which defines Xi as the "core" leader of the party and cements his ideas as the guiding principles of China's future development; "Two Safeguards", which assures Xi's "core" status within the party and the party's centralized authority over China; developing "fighting spirit", strengthening fighting ability; promoting "Chinese-style modernization"; gradually achieving "common prosperity"; developing a broader, fuller and more robust "whole-process people’s democracy"; requiring political loyalty in the military; opposing and deterring separatists seeking Taiwan independence; recognizing the party as the "supreme political leadership force"; obliging all party members to learn the party's history.