Julian Lenz (born 17 February 1993 in Giessen) is a German tennis player.

He has an ATP career high singles ranking of world No.

Lenz won the 2011 US Open boys' doubles title, partnering Robin Kern.

He made his ATP Tour main draw debut by qualifying for both singles and doubles at the 2019 Hamburg European Open.

[1] In doubles, he and partner Daniel Masur upset compatriots Alexander and Mischa Zverev after saving two match points in the opening round.