The ruling Communist Party proposed the amendment last month and there was never any doubt it would pass as parliament is packed with loyal party members who would not have opposed the proposal.
The vote passed with two “no” votes, three abstentions and one invalidated vote among nearly 3,000 delegates.
The 64-year-old leader began his second five-year term as party chief in October and at the end of the week will be formally appointed by parliament.
The limit of two five-year presidential terms was written into China’s constitution after Mao Zedong’s death in 1976. The system was enacted by Deng Xiaoping, who recognised the dangers of one-man rule and the cult of personality and instead espoused collective leadership.
The government has said lifting the term limits is about protecting the authority of the party with Mr Xi at its centre.
The party’s official People’s Daily has said this does not mean life-long terms.
The party gave Mr Xi the title of “core” leader in 2016, a significant strengthening of his position at the time.
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While the presidency is important, Mr Xi’s positions as head of the party and head of the military are considered more important, and these titles are always given first by state media.
With the passage of the amendment, now none of the posts have formal term limits.
The amendments also include inserting Mr Xi’s political theory into the constitution, something that was already done for the party constitution in October, and clauses to give a legal framework to a new anti-corruption department.