| Date: | 19–25 May |
| Edition: | 67th |
| Category: | Grand Prix circuit (AA grade) |
| Surface: | Clay / outdoor |
| Draw: | 64S / 32D |
| Prize Money: | $100,000 |
| Location: | Hamburg, West Germany |
| Attendance: | 38,000 |
| Champms: |  Manuel Orantes[1] |
| Champws: | Renáta Tomanová |
| Champmd: | Juan Gisbert / Manuel Orantes[2] |
| Champwd: |  Dianne Fromholtz / Renáta Tomanová |
| After Name: | German Open (tennis) |
The 1975 Grand Prix German Open was a combined men's and women's tennis tournament played on outdoor red clay courts. It was the 67th edition of the event and was part of the 1975 Commercial Union Assurance Grand Prix circuit. It took place at the Am Rothenbaum in Hamburg, West Germany, from 19 May through 25 May 1975. Manuel Orantes and Renáta Tomanová won the singles titles.[3]
Manuel Orantes defeated Jan Kodeš 3–6, 6–2, 6–2, 4–6, 6–1
Renáta Tomanová defeated 
Kazuko Sawamatsu 7–6, 5–7, 10–8
Juan Gisbert / Manuel Orantes defeated 
Wojciech Fibak / Jan Kodeš 6–3, 7–6
Dianne Fromholtz / Renáta Tomanová defeated 
Paulina Peisachov / Kazuko Sawamatsu 6–3, 6–2