| Champ: |  Dominic Thiem |
| Score: | 6–2, 6–4 |
| Draw: | 28 (4 / 3) |
| Seeds: | 8 |
| Type: | singles doubles |
| Before Name: | Argentina Open – Singles |
| After Name: | Argentina Open – Singles |
See main article: 2018 Argentina Open.
Alexandr Dolgopolov was the defending champion, but withdrew before the tournament began.
Dominic Thiem won the title, defeating Aljaž Bedene in the final, 6–2, 6–4.
The top four seeds receive a bye into the second round.