Captain Shelina Zadorsky will be at Tottenham until 2023 after she took up the option of a one-year extension in her contract.
Canada defender Zadorsky, 29, signed a new deal in 2021 that was due to expire in June.
She has formed a formidable central defensive partnership with Molly Bartrip this season.
"I'm just excited. Coming here to the WSL has been such a good decision for me and my career," Zadorsky said.
Zadorsky joined Tottenham in 2020, initially on loan from Orlando Pride, and won gold at last summer's Olympic Games.
She has started 17 of Tottenham's 18 Women's Super League games this season and helped them to fifth in the table.
"I just want to keep growing and it's a huge honour to play for the club," added Zadorksky.