Ter Stegen became Barca’s No.1 last season replacing Claudio Bravo, starting 36 games in La Liga and nine in the Champions League, being selected ahead of Jasper Cillessen.
The 25-year-old signed for Barcelona from Bundesliga side Borussia Monchengladbach in 2014 and has won nine trophies since his move.
A Champions League triumph, two La Ligas and three Copa del Reys are included in that total.
He recorded a better save success rate than any other La Liga goalkeeper who started 10 or more games last season, stopping 79.2 per cent of efforts fired towards him.
A club statement read: “Barcelona has reached an agreement with the player Marc-Andre ter Stegen to extend and improve his contract until 30 June 2022.
“His buy-out clause now stands at 180 million euros. His new contract will be signed on Tuesday 30 May at 1.30pm CET at the club offices.”