| Date: | 20–26 July |
| Edition: | 103rd |
| Category: | ATP World Tour 500 |
| Prize Money: | €1,000,000 |
| Draw: | 48S / 16D |
| Surface: | Clay / outdoor |
| Location: | Hamburg, Germany |
| Champs: |  Nikolay Davydenko[1] |
| Champd: |  Simon Aspelin /  Paul Hanley[2] |
The 2009 International German Open was a men's tennis tournament played on outdoor red clay courts. It was the 103rd edition of the event known that year as the International German Open and was part of the ATP World Tour 500 series of the 2009 ATP World Tour. It took place at the Am Rothenbaum in Hamburg, Germany, from 20 July through 26 July 2009.[3]
| Player | Nation | Ranking* | Seeding |
|---|---|---|---|
| Gilles Simon |  France | 7 | 1 |
| Nikolay Davydenko | Russian Federation | 11 | 2 |
| Robin Söderling | Sweden | 12 | 3 |
| Tommy Robredo |  Spain | 16 | 4 |
| Stanislas Wawrinka | 19 | 5 | |
| David Ferrer | Spain | 23 | 6 |
| Igor Andreev | Russian Federation | 25 | 7 |
| Philipp Kohlschreiber | 26 | 8 | |
| Jürgen Melzer |  Austria | 28 | 9 |
| Viktor Troicki |  Serbia | 29 | 10 |
| Victor Hănescu |  Romania | 33 | 11 |
| José Acasuso |  Argentina | 37 | 12 |
| Paul-Henri Mathieu | France | 39 | 13 |
| Nicolás Almagro | Spain | 41 | 14 |
| Jérémy Chardy | France | 43 | 15 |
| Mischa Zverev | 45 | 16 | |
The following players received wildcards into the singles main draw
The following players received entry from the qualifying draw:
See main article: 2009 International German Open – Singles. Nikolay Davydenko defeated Paul-Henri Mathieu, 6–4, 6–2
See main article: 2009 International German Open – Doubles. Simon Aspelin / Paul Hanley defeated 
Marcelo Melo / 
Filip Polášek, 6–3, 6–3
