| Date: | 5–11 November |
| Edition: | 19th |
| Category: | ATP Challenger Tour |
| Location: | Bratislava, Slovakia |
| Champs: |  Alexander Bublik |
| Champd: |  Denys Molchanov /  Igor Zelenay |
The 2018 Slovak Open was a professional tennis tournament played on indoor hard courts. It was the 19th edition of the tournament which was part of the 2018 ATP Challenger Tour. It took place in Bratislava, Slovakia between 5 and 11 November 2018.
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
| Slovakia | Lukáš Lacko | 82 | 1 | |
 Russian Federation | Evgeny Donskoy | 100 | 2 | |
 Italy | Lorenzo Sonego | 105 | 3 | |
 Spain | Guillermo García López | 106 | 4 | |
 Argentina | Marco Trungelliti | 118 | 5 | |
 India | Ramkumar Ramanathan | 121 | 6 | |
 Cyprus | Marcos Baghdatis | 127 | 7 | |
 Belgium | Ruben Bemelmans | 129 | 8 |
The following players received wildcards into the singles main draw:
Norbert Gombos Lukáš Klein Tomáš Líška Alex MolčanThe following player received entry into the singles main draw using a protected ranking:
The following players received entry into the singles main draw as alternates:
The following players received entry from the qualifying draw:
See main article: 2018 Slovak Open – Singles.
Alexander Bublik def. 
Lukáš Rosol 6–4, 6–4.See main article: 2018 Slovak Open – Doubles.
Denys Molchanov / Igor Zelenay def. Ramkumar Ramanathan / 
Andrei Vasilevski 6–2, 3–6, [11–9].