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The new deal does not extend Conte's commitment to the club, as he signed a three-year contract on his arrival in west London in the summer of 2016.
"I am very happy to have signed a new contract," said the Italian, 47.
"We worked extremely hard in our first year to achieve something amazing, which I am very proud of. Now we must work even harder to stay at the top."
The decision to sign a new contract without extending the terms runs counter to previous comments by Conte, who had indicated his willingness to commit to a longer deal.
Speaking in May, he said he wanted to stay with Chelsea "for many years", adding: "If the club give me the possibility to stay and extend my contract, for sure I'm available to."
Conte lifted the Premier League title at the first attempt in the 2016-17 season, winning 30 games, which included a club record 13 consecutive victories. He also guided the Blues to the FA Cup final, though they were beaten by Arsenal.
The former Juventus and Italy manager was credited for transforming the Stamford Bridge club's fortunes after they could only finish 10th the previous season.
A brutal training regime was part of the transformation, as was his decision to switch to a three-man central-defensive set-up - his preferred tactic at both Juve and Italy.
"The Chelsea fans have given me so much support since I arrived here one year ago and it is important we continue to succeed together," added Conte, whose team has flown out to China and Singapore for pre-season games against the Gunners, Bayern Munich and Inter Milan.
Chelsea director Marina Granovskaia added: "Antonio achieved incredible success last season, adapting to English football very quickly and leading us to the Premier League title.
"This new contract reflects our belief that he can continue to deliver results both domestically and as we return to European competition in the Champions League."
Conte has presided over at busy summer so far at Stamford Bridge.
Blues have signed midfielder Tiemoue Bakayoko from French champions Monaco in a reported £40m deal, and also brought in defender Antonio Rudiger from Roma for an initial £29m.
The Chelsea boss was thwarted in the chase to take striker Romelu Lukaku from Everton, with the Belgium international instead joining Manchester United in a £75m deal.
Conte has also been working hard to get players out the door at Stamford Bridge, with striker Diego Costa and midfielder Nemanja Matic both absent from the Far East tour before expected moves.
Chelsea manager Antonio Conte has signed an improved two-year deal with the Premier League champions.