The 2023 Ostra Group Open was a professional tennis tournament played on clay courts. It was the 20th edition of the tournament which was part of the 2023 ATP Challenger Tour. It took place in Ostrava, Czech Republic between 24 and 30 April.
Singles main-draw entrants
Seeds
1 Rankings are as of 17 April 2023.
Other entrants
The following players received wildcards into the singles main draw: Jakub Menšík Gaël Monfils Jiří Veselý
The following players received entry into the singles main draw as alternates: Shintaro Mochizuki Vitaliy Sachko
The following players received entry from the qualifying draw: Guido Andreozzi Àlex Martí Pujolràs Rudolf Molleker Patrik Rikl Henri Squire Khumoyun Sultanov
Champions
Singles
Zdeněk Kolář def. Máté Valkusz 6–3, 6–2.
Doubles
Robert Galloway / Miguel Ángel Reyes-Varela def. Guido Andreozzi / Guillermo Durán 7–5, 7–6(7–5).