The 24-year-old Germany international, linked with a move to Chelsea and Liverpool, has had a stellar season, starting all of Bayer’s 21 Bundesliga matches and scoring nine times.
“I’ve improved a lot in my development under coach Roger Schmidt this term,” Bellarabi told his club’s official website. “I’ve become a much better player under his guidance and in his system.”
Bellarabi entered the Bundesliga record books last August when scoring the fastest ever German league goal after just nine seconds against Borussia Dortmund.
“I’ve never enjoyed such trust as Roger Schmidt. I will do everything to repay him and Leverkusen,” he said.
He made his full international debut for Germany in October in a 2-0 Euro 2016 qualifying defeat away to Poland.
Leverkusen, who are sixth in the table with only four points separating them and a place in the top three, head to fifth-placed Augsburg on Saturday.