| Date: | 11–17 October |
| Edition: | 4th |
| Surface: | Clay |
| Location: | Villena, Alicante, Spain |
| Venue: | Ferrero Tennis Academy |
| Champs: |  Constant Lestienne |
| Champd: |  Denys Molchanov /  David Vega Hernández |
The 2021 JC Ferrero Challenger Open was a professional tennis tournament played on clay courts. It was the fourth edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place at the Ferrero Tennis Academy in Villena, Alicante, Spain, between 11 and 17 October 2021.
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
| Spain | Feliciano López | 108 | 1 | |
| Spain | Fernando Verdasco | 137 | 2 | |
| Oscar Otte | 138 | 3 | ||
| France | Quentin Halys | 158 | 4 | |
 Kazakhstan | Dmitry Popko | 165 | 5 | |
 Poland | Kacper Żuk | 172 | 6 | |
| Spain | Mario Vilella Martínez | 173 | 7 | |
| João Sousa | 182 | 8 |
The following players received wildcards into the singles main draw:
The following players received entry into the singles main draw as alternates:
The following players received entry from the qualifying draw:
Sriram Balaji Georgii Kravchenko
Santiago Rodríguez Taverna Denis YevseyevSee main article: 2021 JC Ferrero Challenger Open – Singles.
Constant Lestienne def. Hugo Grenier 6–4, 6–3.See main article: 2021 JC Ferrero Challenger Open – Doubles.
Denys Molchanov / David Vega Hernández def. Romain Arneodo / 
Matt Reid 6–4, 6–2.
