The 28-year-old made 61 appearances for Chelsea since joining from Monaco in 2023.
Disasi had a loan spell with West Ham United last season, making 14 Premier League appearances for them.
"I'm very happy. The club has been going in a very good direction, so I think it was the right place for me to keep going," Disasi said in a statement.
The France international was part of the squad that reached the 2022 World Cup final in Qatar.