The 2019 AON Open Challenger was a professional tennis tournament played on clay courts. It was the seventeenth edition of the tournament which was part of the 2019 ATP Challenger Tour. It took place in Genoa, Italy between 2 and 8 September 2019.
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
 Italy | Lorenzo Sonego | 49 | 1 | |
 Spain | Albert Ramos Viñolas | 51 | 2 | |
| Italy | Marco Cecchinato | 66 | 3 | |
| Philipp Kohlschreiber | 71 | 4 | ||
| Spain | Roberto Carballés Baena | 76 | 5 | |
| Italy | Stefano Travaglia | 81 | 6 | |
| Spain | Jaume Munar | 97 | 7 | |
 Brazil | Thiago Monteiro | 101 | 8 | |
| Italy | Salvatore Caruso | 102 | 9 | |
 Argentina | Guido Andreozzi | 106 | 10 | |
| Spain | Alejandro Davidovich Fokina | 126 | 11 | |
| Italy | Lorenzo Giustino | 128 | 12 | |
 Hungary | Attila Balázs | 130 | 13 | |
 Japan | Taro Daniel | 136 | 14 | |
 Belgium | Kimmer Coppejans | 138 | 15 | |
 Czech Republic | Jiří Veselý | 140 | 16 |
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:
See main article: 2019 AON Open Challenger – Singles.
Lorenzo Sonego def. Alejandro Davidovich Fokina 6–2, 4–6, 7–6(8–6).See main article: 2019 AON Open Challenger – Doubles.
Gonzalo Escobar def. Guido Andreozzi / Andrés Molteni 3–6, 6–4, [10–3].