1990 ATP German Open
| 1990 ATP German Open | |
|---|---|
| Date | 7–14 May |
| Edition | 84th |
| Category | ATP Super 9 |
| Prize money | $750,000 |
| Surface | Clay / outdoor |
| Location | Hamburg, Germany |
| Venue | Rothenbaum Tennis Center |
| Champions | |
| Singles | |
 Juan Aguilera [1] | |
| Doubles | |
Sergi Bruguera /  Jim Courier [2] | |
The 1990 German Open was a men's tennis tournament played on outdoor clay courts. It was the 84th edition of the Hamburg Masters (Hamburg Masters), and was part of the ATP Super 9 of the 1990 ATP Tour. It took place at the Rothenbaum Tennis Center in Hamburg, Germany, from 7 May through 14 May 1990.
The men's field was headlined by ATP No. 3, Brussels, Stuttgart titlist, Australian Open, Monte Carlo quarter-finalist Boris Becker, Miami, San Francisco winner, recent Indian Wells finalist Andre Agassi and Tokyo Outdoor winner and U.S. Open semi-finalist Aaron Krickstein. Other top seeds were Estoril titlist Emilio Sánchez, Jay Berger, Andrés Gómez and Michael Chang.
Finals
Singles
Juan Aguilera defeated 
Boris Becker, 6–1, 6–0, 7–6,
- It was Juan Aguilera's 2nd title of the year, and his 5th overall. It was his 1st Masters title of the year, and overall.
Doubles
Sergi Bruguera / Jim Courier defeated Udo Riglewski / Michael Stich, 7–6, 6–2