Matheus Tobias Leist (born September 8, 1998) is a Brazilian racing driver for A.J. Foyt Enterprises in the IndyCar Series.
Leist began karting in 2009 at the age of eleven. In 2013, he finished as runner-up in the Petrobras Karting Championship. In 2014, Leist graduated to single-seaters, racing in the B class of the Brazilian F3 Championship, finishing runner-up to Vitor Baptista. The following year, Leist switched to MSA Formula in Britain with Double R Racing. He scored two victories and finished fifth in the standings.
In 2016, Leist reunited with Double R Racing and graduated to BRDC British F3. Scoring four wins, two poles and six fastest laps, Leist took the title at the final round after a close fight with Ricky Collard throughout the season.
In November 2017, A.J. Foyt Enterprises announced that the team hired Leist to drive the No. 4 Chevrolet in 2018. Leist partners veteran Brazilian driver Tony Kanaan and made his IndyCar debut at the Firestone Grand Prix of St. Petersburg on March 11, 2018.