The 2018 The Hague Open was a professional tennis tournament played on clay courts. It was the 26th edition of The Hague Open and was part of the 2018 ATP Challenger Tour. It took place in Scheveningen, Netherlands between 16 and 22 July 2018.
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
| Yannick Maden | 134 | 1 | ||
 Czech Republic | Adam Pavlásek | 145 | 2 | |
| Mats Moraing | 156 | 3 | ||
| Oscar Otte | 166 | 4 | ||
 Italy | Matteo Donati | 176 | 5 | |
 Argentina | ||||
 Hungary | Attila Balázs | 182 | 7 | |
 France | Grégoire Barrère | 188 | 8 |
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:
See main article: 2018 The Hague Open – Singles.
See main article: 2018 The Hague Open – Doubles.
Nathaniel Lammons def. 
Luis David Martínez / Gonçalo Oliveira 6–3, 6–7(8–10), [10–5].
