| Doubles | |
|---|---|
| 2020 Sibiu Open | |
| Champions |  Hunter Reese  Jan Zieliński |
| Runners-up | Robert Galloway  Hans Hach Verdugo |
| Score | 6–4, 6–2 |
Sadio Doumbia and Fabien Reboul were the defending champions [1] but chose not to defend their title.
Hunter Reese and Jan Zieliński won the title after defeating Robert Galloway and Hans Hach Verdugo 6–4, 6–2 in the final.
Luis David Martínez / Miguel Ángel Reyes-Varela (quarterfinals)
Felipe Meligeni Alves / Fernando Romboli (semifinals)
Treat Huey / Nathaniel Lammons (first round)
Andre Begemann / 
Florin Mergea (quarterfinals)| First round | Quarterfinals | Semifinals | Final | ||||||||||||||||||||||||
| 1 | LD Martínez MÁ Reyes-Varela | 6 | 6 | ||||||||||||||||||||||||
| WC | D Dima  E Kırkın | 3 | 2 | 1 | LD Martínez MÁ Reyes-Varela | 3 | 64 | ||||||||||||||||||||
| O Luz R Matos | 4 | 3 |  A Göransson  M-A Hüsler | 6 | 77 | ||||||||||||||||||||||
| A Göransson M-A Hüsler | 6 | 6 | A Göransson M-A Hüsler | 63 | 6 | [6] | |||||||||||||||||||||
| 3 | T Huey N Lammons | 6 | 62 | [7] | R Galloway H Hach Verdugo | 77 | 3 | [10] | |||||||||||||||||||
| R Galloway H Hach Verdugo | 2 | 77 | [10] | R Galloway H Hach Verdugo | 6 | 6 | |||||||||||||||||||||
| A Lawson K Żuk | 5 | 6 | [9] | Alt |  F Cerúndolo TM Etcheverry | 0 | 4 | ||||||||||||||||||||
| Alt | F Cerúndolo TM Etcheverry | 7 | 3 | [11] | R Galloway H Hach Verdugo | 4 | 2 | ||||||||||||||||||||
| H Reese J Zieliński | 6 | 6 | H Reese J Zieliński | 6 | 6 | ||||||||||||||||||||||
| WC | Tudor Ștefan Gheorghiță DN Mădăraș | 4 | 1 | H Reese J Zieliński | 6 | 6 | |||||||||||||||||||||
| PR |  Í Cervantes O Roca Batalla | 1 | 2 | 4 | A Begemann F Mergea | 4 | 4 | ||||||||||||||||||||
| 4 | A Begemann F Mergea | 6 | 6 | H Reese J Zieliński | 6 | 7 | |||||||||||||||||||||
| WC | VV Cornea A Jecan | 4 | 2 | 2 | F Meligeni Alves F Romboli | 3 | 5 | ||||||||||||||||||||
A Menéndez Maceiras  L Miedler | 6 | 6 | A Menéndez Maceiras L Miedler | 63 | 5 | ||||||||||||||||||||||
 B Lock R Ortega Olmedo | 60 | 3 | 2 | F Meligeni Alves F Romboli | 77 | 7 | |||||||||||||||||||||
| 2 | F Meligeni Alves F Romboli | 77 | 6 | ||||||||||||||||||||||||
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