Justin Engel (born 1 October 2007) is a German tennis player.

Engel has a career-high ATP singles ranking of world No.

[2] In May, at the age of 16, Engel became the youngest German men's title winner since 2003 when he won an ITF World Tennis Tour tournament in Villach, Austria.

[3] Engel made his ATP Challenger Tour main draw debut at the Tennis Open Karlsruhe, having received a wildcard.

He defeated Coleman Wong in straight sets to claim his first ATP Tour main draw win, becoming the youngest player to do so since Carlos Alcaraz at the 2020 Rio Open and the first player born in the year 2007 to win an ATP match.