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,^[2] but losing to Anett Kontaveit in the first round.^[3]

Result	W–L	Date	Tournament	Tier	Surface	Opponent	Score
Win	1–0	Aug 2021	ITF Erwitte, Germany	W15	Clay	Sofia Samavati	3–6, 7–5, 6–2
Loss	1–1	Nov 2021	ITF Monastir, Tunisia	W15	Hard	Ma Yexin	4–6, 2–6
Win	2–1	Apr 2022	ITF Antalya, Turkey	W15	Clay	Victoria Kan	6–1, 4–1 ret.
Win	3–1	Aug 2022	ITF Erwitte, Germany	W15	Clay	Martha Matoula	3–6, 6–3, 6–4
Loss	3–2	Jul 2023	ITF Stuttgart, Germany	W25	Clay	Ella Seidel	3–6, 1–6
Loss	3–3	Aug 2023	ITF Braunschweig, Germany	W25	Clay	Ella Seidel	6–7(4), 3–6

Result	W–L	Date	Tournament	Tier	Surface	Partner	Opponents	Score
Loss	0–1	Nov 2021	ITF Monastir, Tunisia	W15	Hard	Mariana Dražić	Yasmine Mansouri Elena Milovanović	6–7(4), 0–6
Loss	0–2	Mar 2022	ITF Gonesse, France	W15	Clay (i)	Nicole Rivkin	Flavie Brugnone Tamara Čurović	2–6, 3–6

• Julia Middendorf at the Women's Tennis Association
• Julia Middendorf at the International Tennis Federation