The former Germany youth international has missed just one game for Brighton all season as the Seagulls continue their push for European football.
Gross joined Brighton from Ingolstadt in the summer of 2017 and has made 184 appearances, scoring 23 goals and making 33 assists.
He is the latest Brighton player to extend his stay at the AMEX Stadium in recent months, joining the likes of Solly March, Moises Caicedo and Adam Lallana.
"We’re delighted to announce that Pascal Gross has committed his long-term future to the Albion by agreeing a new contract that runs until 2025," a statement from Brighton read.
"The 31-year-old German midfielder has been with us since we came into the Premier League in 2017 and has now made 184 league appearances for Albion and contributed 23 goals and 33 assists."
Brighton boss Roberto De Zerbi added: “I am absolutely delighted that Pascal has agreed a new contract with us.
“He is one of best players I have worked with during my career and every day I appreciate him more and more.
“He is one of the secrets to Albion’s success.”
Brighton are in action against Manchester United in the FA Cup semi-finals on Sunday.
