The 2020 Split Open was a professional tennis tournament played on clay courts. It was part of the 2020 ATP Challenger Tour. It took place in Split, Croatia between 28 September and 4 October 2020.
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
| Pedro Sousa | 113 | 1 | ||
 Slovakia | Jozef Kovalík | 124 | 2 | |
| Bradley Klahn | 134 | 3 | ||
 Spain | Carlos Taberner | 148 | 4 | |
 Serbia | Danilo Petrović | 159 | 5 | |
| Slovakia | Martin Kližan | 162 | 6 | |
| Botic van de Zandschulp | 165 | 7 | ||
 Japan | Tatsuma Ito | 166 | 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 players received entry from the qualifying draw:
See main article: 2020 Split Open – Singles.
Francisco Cerúndolo def. Pedro Sousa 4–6, 6–3, 7–6(7–4).See main article: 2020 Split Open – Doubles.
Nathaniel Lammons def. 
André Göransson / Hunter Reese 6–4, 7–6(7–3).
