The 2021 Aspria Tennis Cup was a professional tennis tournament played on clay courts. It was the fifteenth edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Milan, Italy between 21 and 27 June 2021.
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
 Argentina | Federico Coria | 103 | 1 | |
| Holger Rune | 231 | 2 | ||
| Ulises Blanch | 247 | 3 | ||
| Argentina | Facundo Mena | 249 | 4 | |
| Gastão Elias | 250 | 5 | ||
 France | Tristan Lamasine | 252 | 6 | |
 Russian Federation | Teymuraz Gabashvili | 256 | 7 | |
 Italy | Gian Marco Moroni | 260 | 8 |
The following players received wildcards into the singles main draw:
The following player received entry into the singles main draw as a special exempt:
The following player received entry into the singles main draw using a protected ranking:
The following player received entry into the singles main draw as an alternate:
The following players received entry from the qualifying draw:
See main article: 2021 Aspria Tennis Cup – Singles.
Gian Marco Moroni def. Federico Coria 6–3, 6–2.See main article: 2021 Aspria Tennis Cup – Doubles.
Vít Kopřiva / Jiří Lehečka def. Dustin Brown / 
Tristan-Samuel Weissborn 6–4, 6–0.