Julia Middendorf (born 31 January 2003) is a German tennis player.
Middendorf has a career-high WTA singles ranking of 347, achieved in August 2023, and a best doubles ranking of No. 610, reached in November 2022.
She made her WTA Tour main-draw debut at the 2021 Stuttgart Open, after defeating Jana Fett and Tamara Korpatsch in the qualifying, but losing to Anett Kontaveit in the first round.