| Date: | 9–15 October (men) 30 October – 5 November (women) |
| Edition: | 25th (men) 10th (women) |
| Category: | ATP Challenger Tour ITF Women's World Tennis Tour |
| Surface: | Hard (Indoor) |
| Location: | Bratislava, Slovakia |
| Champms: |  Gabriel Diallo |
| Champmd: |  Sriram Balaji / Andre Begemann |
| Champws: | Ella Seidel |
| Champwd: |  Estelle Cascino /  Jesika Malečková |
The 2023 Slovak Open was a professional tennis tournament played on hard courts. It was the 25th edition of the tournament which was part of the 2023 ATP Challenger Tour and the tenth edition of the tournament which was part of the 2023 ITF Women's World Tennis Tour. It took place in Bratislava, Slovakia between 9 and 15 October 2023 for the men and 30 October and 5 November for the women.
See main article: 2023 Slovak Open – Men's singles.
Gabriel Diallo def. 
Joris De Loore 6–0, 7–5.See main article: 2023 Slovak Open – Women's singles.
See main article: 2023 Slovak Open – Men's doubles.
Sriram Balaji / Andre Begemann def. 
Andrey Golubev / 
Denys Molchanov 6–3, 5–7, [10–8].See main article: 2023 Slovak Open – Women's doubles.
Estelle Cascino / Jesika Malečková def. Denisa Hindová / Karolína Kubáňová, 6–3, 6–2| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
 Austria | Dominic Thiem | 72 | 1 | |
| Dominic Stricker | 88 | 2 | ||
| France | Benjamin Bonzi | 89 | 3 | |
| Czech Republic | ||||
 United Kingdom | Liam Broady | 104 | 5 | |
 Hungary | Zsombor Piros | 109 | 6 | |
 United States | Maxime Cressy | 112 | 7 | |
 Slovakia | Alex Molčan | 113 | 8 |
The following players received wildcards into the singles main draw:
Norbert Gombos Andrew Paulson Lukáš PokornýThe following player received entry into the singles main draw using a protected ranking:
The following players received entry into the singles main draw as special exempts:
The following players received entry from the qualifying draw:
The following players received entry as lucky losers:
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
 Australia | ||||
| Slovakia | Rebecca Šramková | 129 | 2 | |
| Hungary | Dalma Gálfi | 154 | 3 | |
| Jule Niemeier | 175 | 4 | ||
| France | Chloé Paquet | 186 | 5 | |
| Sofya Lansere | 221 | 6 | ||
| Ella Seidel | 232 | 7 | ||
| Lea Bošković | 243 | 8 |
The following players received wildcards into the singles main draw:
Renáta Jamrichová Katarína Kužmová Eszter Méri Nina VargováThe following players received entry from the qualifying draw:
Mia Pohánková Katarína Strešnáková Radka ZelníčkováThe following players received entry as lucky losers:
Aneta Laboutková Emma Tóthová
