The 2018 Lyon Open (also known as the Open Parc Auvergne-Rhône-Alpes Lyon) was a men's tennis tournament played on outdoor clay courts. It was the second edition of the Lyon Open and part of the ATP World Tour 250 series of the 2018 ATP World Tour. It took place in the city of Lyon, France, from May 20 through May 26, 2018.[1]
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
 Austria | Dominic Thiem | 8 | 1 | |
 United States | John Isner | 10 | 2 | |
| United States | Jack Sock | 15 | 3 | |
 Korea, Republic of | ||||
 France | Adrian Mannarino | 27 | 5 | |
| France | Gaël Monfils | 38 | 6 | |
| João Sousa | 48 | 7 | ||
 Australia |
The following players received wildcards into the singles main draw:
The following players received entry from the qualifying draw:
The following players received entry as lucky losers:
Chung Hyeon → replaced by 
Joris De Loore
Karen Khachanov → replaced by 
Cameron Norrie
Leonardo Mayer → replaced by 
Mikhail Kukushkin Daniil Medvedev → replaced by 
Dušan Lajović Viktor Troicki → replaced by Calvin Hemery Jo-Wilfried Tsonga → replaced by Federico Coria| Country | Player | Country | Player | Rank1 | Seed | |
|---|---|---|---|---|---|---|
 Pakistan | Aisam-ul-Haq Qureshi | Jean-Julien Rojer | 42 | 1 | ||
 India | Rohan Bopanna | France | Édouard Roger-Vasselin | 50 | 2 | |
| Julio Peralta | Argentina | Horacio Zeballos | 69 | 3 | ||
 Poland | Marcin Matkowski |  Japan | Ben McLachlan | 70 | 4 |
The following pairs received wildcards into the doubles main draw:
See main article: 2018 ATP Lyon Open – Singles.
Dominic Thiem defeated Gilles Simon, 3–6, 7–6(7–2), 6–1See main article: 2018 ATP Lyon Open – Doubles.
Nick Kyrgios / Jack Sock defeated 
Roman Jebavý / Matwé Middelkoop, 7–5, 2–6, [11–9]
