| Challenger - Vicenza | 05/31 12:40 | 26 | [159] Lorenzo Giustino v Benjamin Hassan [349] | 1-6,3-6 | |
| Challenger - Vicenza | 05/30 16:30 | 25 | [159] Lorenzo Giustino v Gonzalo Escobar [321] | 6-7,6-2,7-5 | |
| French Open | 05/20 15:20 | 44 | [209] Pedja Krstin v Lorenzo Giustino [157] | 6-4,6-2 | |
| Challenger - Lisabon | 05/18 10:40 | 28 | [165] Lorenzo Giustino v Facundo Bagnis [144] | Retired | |
| Challenger - Lisabon | 05/17 12:00 | 27 | [473] Sandro Ehrat v Lorenzo Giustino [165] | 5-7,6-3,2-6 | |
| Challenger - Lisabon | 05/16 09:00 | 26 | [165] Lorenzo Giustino v Bjorn Fratangelo [136] | 6-4,2-6,6-2 | |
| Challenger - Lisabon | 05/15 09:00 | 25 | [165] Lorenzo Giustino v Zdeněk Kolář [213] | 6-4,6-2 | |
| Challenger - Aix en Provence | 05/07 16:25 | 25 | [161] Lorenzo Giustino v Viktor Troicki [252] | 6-4,2-6,4-6 | |
| ATP - Estoril | 04/27 11:00 | 64 | [86] Daniel Evans v Lorenzo Giustino [164] | 6-3,7-5 | |
| Challenger - Tunisko | 04/20 13:15 | 28 | [81] Pablo Cuevas v Lorenzo Giustino [173] | 6-2,6-4 | |
| Challenger - Tunisko | 04/19 13:20 | 27 | [212] Facundo Arguello v Lorenzo Giustino [173] | 6-2,3-6,4-6 | |
| Challenger - Tunisko | 04/18 13:25 | 26 | [173] Lorenzo Giustino v Johan Tatlot [260] | 6-1,5-7,6-3 | |
| Challenger - Tunisko | 04/16 10:35 | 25 | [173] Lorenzo Giustino v Zdeněk Kolář [219] | 6-1,6-3 | |
| Challenger - Barletta | 04/11 11:30 | 26 | [487] Jacopo Berrettini v Lorenzo Giustino [169] | 4-6,7-6,6-4 | |
| Challenger - Barletta | 04/10 10:55 | 25 | [359] Andrea Pellegrino v Lorenzo Giustino [169] | Retired | |
| Challenger - Alicante | 04/03 08:00 | 25 | [167] Lorenzo Giustino v Elias Ymer [115] | 6-2,4-6,2-6 | |
| Challenger - Alicante | 04/01 16:30 | 24 | [284] Goncalo Oliveira v Lorenzo Giustino [167] | 6-3,4-6,3-6 | |
| Challenger - Zhangjiagang | 03/24 04:40 | 29 | [189] Lorenzo Giustino v Marc Polmans [200] | 4-6,6-4,6-7 | |
| Challenger - Zhangjiagang | 03/23 06:15 | 28 | Viktor Galovic v Lorenzo Giustino | Walkover | |
| Challenger - Zhangjiagang | 03/22 04:15 | 27 | [169] Soonwoo Kwon v Lorenzo Giustino [189] | 3-6,2-6 | |
| Challenger - Zhangjiagang | 03/21 07:45 | 26 | [257] Max Purcell v Lorenzo Giustino [189] | 3-6,4-6 | |
| Challenger - Zhangjiagang | 03/19 05:45 | 25 | Daniel Nguyen v Lorenzo Giustino | 0-6,3-6 | |
| Challenger - Šen-čen | 03/14 11:30 | 26 | [106] Brayden Schnur v Lorenzo Giustino [189] | 4-6,7-5,6-2 | |
| Challenger - Šen-čen | 03/12 05:45 | 25 | [406] Javier Barranco Cosano v Lorenzo Giustino [189] | 3-6,4-6 | |
| Challenger - Pau | 02/27 11:40 | 25 | [275] Lucas Miedler v Lorenzo Giustino [189] | 4-6,7-6,6-4 | |
| Challenger - Bergamo | 02/21 10:40 | 26 | [152] Luca Vanni v Lorenzo Giustino [185] | 6-3,6-1 | |
| Challenger - Bergamo | 02/19 12:45 | 25 | [222] Zdeněk Kolář v Lorenzo Giustino [185] | 2-6,1-6 | |
| Challenger - Launceston | 02/03 01:30 | 29 | [111] Lloyd Harris v Lorenzo Giustino [227] | 6-2,6-2 | |
| Challenger - Launceston | 02/02 02:00 | 28 | [360] Luke Saville v Lorenzo Giustino [227] | 6-7,6-2,5-7 | |
| Challenger - Launceston | 02/01 03:35 | 27 | [227] Lorenzo Giustino v Jay Clarke [212] | Retired |
Lorenzo Giustino (Italian pronunciation: [loˈrɛntso dʒuˈstiːno]; born 10 September 1991, in Naples) is an Italian tennis player.
Giustino has a career-high ATP singles ranking of 127 achieved on 12 August 2019 and a career-high ATP doubles ranking of 311 achieved on 15 April 2019.
Giustino made his ATP main draw debut at the 2015 BRD Năstase Țiriac Trophy, where he qualified for the main draw.
Giustino made his Grand Slam debut at the 2020 Australian Open. He defeated Frenchman Corentin Moutet 0–6, 7–6 (7), 7–6 (3), 2–6, 18–16 in the first round of 2020 French Open as a first time main draw qualifier at this Major. The match was the second-longest in French Open history, lasting 6 hours, 5 minutes. It was his first ATP tour-level win.
He qualified for his first ATP 500 tournament at the 2021 Dubai Tennis Championships as a lucky loser receiving a bye into the second round after the withdrawal of tenth seed Borna Ćorić.
He qualified for his second ATP 500 at the 2023 Barcelona Open Banc Sabadell.