The Argentine, who has led Spurs to three successive top-three finishes in the Premier League, has penned fresh terms to keep him in north London until 2023.
"I am honoured to have signed a new long-term contract as we approach one of the most significant periods in the club's history and be the manager that will lead this team into our new world-class stadium," he was quoted as saying on the club's official website.
"This is just one of the factors that makes this one of the most exciting jobs in world football and we are already making plans to ensure we continue to build on the great work that everyone has contributed to over the past four years."
Chairman Daniel Levy said the club had been on an "extraordinary journey".
"Mauricio has fostered an incredible spirit in the team and has embraced a style of play our fans have loved watching," he said. "I know they will welcome this commitment by Mauricio."
Pochettino, who joined the club from Southampton in 2014, sparked speculation over his future in the closing weeks of the English season.
Following the FA Cup semi-final defeat against Manchester United, he hinted at a future with somebody else at the helm, even if there was no indication he was intending to step down.
Spurs sealed Champions League football for a third straight season by finishing third in the Premier League despite having reportedly just the sixth highest wage bill behind Manchester City, Manchester United, Chelsea, Arsenal and Liverpool.
Tottenham have also spent only a fraction of the hundreds of millions paid out in the transfer market by the two Manchester clubs, who took the top two spots in the league.
Instead, Pochettino has worked wonders by developing and improving a talented young squad, featuring the likes of England stars Harry Kane and Dele Alli.
But despite their rapid improvement in recent years both domestically and in Europe, Spurs have not won silverware since 2008.
Last week the Argentine, 46, called on Levy to match his ambitions by being "brave" in the transfer market ahead of the moving to a new 62,000-capacity stadium from their temporary home of Wembley.
However, Pochettino's wishes could be hampered by spiralling costs for the new stadium, which reports say could hit £1 billion ($1.3 billion).
First-team coaching staff Jesus Perez, Miguel D'Agostino and Toni Jimenez have also agreed new contracts with the club.