The 2018 Open Harmonie mutuelle was a professional tennis tournament played on hard courts. It was the fifteenth edition of the tournament which was part of the 2018 ATP Challenger Tour. It took place in Saint-Brieuc, France between 26 March and 1 April 2018.
| 2018 Open Harmonie mutuelle | |
|---|---|
| Date | 26 March – 1 April |
| Edition | 15th |
| Draw | 32S / 16D |
| Surface | Hard |
| Location | Saint-Brieuc, France |
| Champions | |
| Singles | |
 Ričardas Berankis | |
| Doubles | |
 Sander Arends /  Tristan-Samuel Weissborn | |
Singles main-draw entrants edit
Seeds edit
| Country | Player | Rank1 | Seed |
|---|---|---|---|
 CYP
|
Marcos Baghdatis | 82 | 1 |
| LTU
|
Ričardas Berankis | 103 | 2 |
 SVK
|
Lukáš Lacko | 104 | 3 |
 UKR
|
Sergiy Stakhovsky | 118 | 4 |
 GER
|
Oscar Otte | 129 | 5 |
 SWE
|
Elias Ymer | 133 | 6 |
 FRA
|
Corentin Moutet | 138 | 7 |
 EST
|
Jürgen Zopp | 147 | 8 |
- Rankings are as of 19 March 2018.
Other entrants edit
The following players received wildcards into the singles main draw:
The following players received entry into the singles main draw as special exempts:
The following players received entry from the qualifying draw:
Champions edit
Singles edit
Ričardas Berankis def. 
Constant Lestienne 6–2, 5–7, 6–4.
Doubles edit
Sander Arends / 
Tristan-Samuel Weissborn def. 
Luke Bambridge / Joe Salisbury 4–6, 6–1, [10–7].
