The 2024 Danube Upper Austria Open was a professional tennis tournament played on clay courts. It was the third edition of the tournament which was part of the 2024 ATP Challenger Tour. It took place in Mauthausen, Austria between 6 and 12 May 2024.

The following players received wildcards into the singles main draw:

The following player received entry into the singles main draw as an alternate:

The following players received entry from the qualifying draw:

The following player received entry as a lucky loser: