# 2021 Hamburg European Open – Men's doubles

John Peers and Michael Venus were the defending champions, but Peers chose not to participate this year.
Venus played alongside Tim Pütz and successfully defended his title, defeating Kevin Krawietz and Horia Tecău in the final, 6–3, 6–7$^{(3–7)}$, [10–8].

## Seeds

* Kevin Krawietz / Horia Tecău (final)
* Tim Pütz / Michael Venus (champions)
* Matwé Middelkoop / Hugo Nys (first round)
* Tomislav Brkić / Nikola Ćaćić (first round)

## Draw
### Key

* Q = Qualifier
* WC = Wild card
* LL = Lucky loser
* Alt = Alternate
* SE = Special exempt
* PR = Protected ranking
* ITF = ITF entry
* JE = Junior exempt
* w/o = Walkover
* r = Retired
* d = Defaulted
* SR = Special ranking

### Draw

| First round | First round | First round | First round | First round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final | Final |
| 1 | K Krawietz H Tecău | 6 | 6 | | | | | | | | | | | | | | |
| LL | R Gonzales H Johnson | 0 | 1 | | 1 | K Krawietz H Tecău | 6 | 6 | | | | | | | | | |
| Q | A Giannessi C Taberner | 3 | 2 | | WC | D Altmeier R Molleker | 3 | 2 | | | | | | | | | |
| WC | D Altmaier R Molleker | 6 | 6 | | | | | | 1 | K Krawietz H Tecău | 6 | 6 | | | | | |
| 3 | M Middelkoop H Nys | 4 | 6 | [8] | | | | | | J Cerretani H Hach Verdugo | 3 | 4 | | | | | |
| | J Cerretani H Hach Verdugo | 6 | 3 | [10] | | J Cerretani H Hach Verdugo | 6 | 6 | | | | | | | | | |
| | I Sabanov M Sabanov | 6 | 6 | | | I Sabanov M Sabanov | 4 | 3 | | | | | | | | | |
| | S Gillé D Sharan | 3 | 4 | | | | | | | | | | 1 | K Krawietz H Tecău | 3 | 7$^7$ | [8] |
| | L Đere G Mager | 3 | 6 | [3] | | | | | | | | | 2 | T Pütz M Venus | 6 | 6$^3$ | [10] |
| | A Behar G Escobar | 6 | 4 | [10] | | A Behar G Escobar | 4 | 4 | | | | | | | | | |
| | A Golubev A Nedovyesov | 6 | 7$^7$ | | | A Golubev A Nedovyesov | 6 | 6 | | | | | | | | | |
| 4 | T Brkić N Ćaćić | 3 | 6$^5$ | | | | | | | A Golubev A Nedovyesov | 3 | 4 | | | | | |
| | F Krajinović D Lajović | 6 | 6 | | | | | | 2 | T Pütz M Venus | 6 | 6 | | | | | |
| | S Balaji L Margaroli | 3 | 2 | | | F Krajinović D Lajović | | | | | | | | | | | |
| WC | P Tsitsipas S Tsitsipas | 5 | 6$^5$ | | 2 | T Pütz M Venus | w/o | | | | | | | | | | |
| 2 | T Pütz M Venus | 7 | 7$^7$ | | | | | | | | | | | | | | |

## Qualifying
### Seeds

* Ruben Gonzales / Hunter Johnson (qualifying competition; lucky losers)
* Alessandro Giannessi / Carlos Taberner (qualified)

### Qualifiers

* Alessandro Giannessi / Carlos Taberner

### Lucky losers

* Ruben Gonzales / Hunter Johnson

### Qualifying draw

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 1 | Ruben Gonzales Hunter Johnson | 6 | 6 | | | | | | |
| WC | Nicola Kuhn Lewie Lane | 1 | 2 | | | | | | |
| WC | Nicola Kuhn Lewie Lane | 1 | 2 | | 1 | Ruben Gonzales Hunter Johnson | 6 | 5 | [8] |
| | | | | | 2 | Alessandro Giannessi Carlos Taberner | 3 | 7 | [10] |
| | Jack Vance Tennyson Whiting | 6$^6$ | 6 | [6] | 2 | Alessandro Giannessi Carlos Taberner | 3 | 7 | [10] |
| 2 | Alessandro Giannessi Carlos Taberner | 7$^8$ | 2 | [10] | | | | | |