| Challenger - Vicenza | 05/29 15:45 | 25 | [175] Lorenzo Giustino v Guido Andreozzi [124] | 6-3,6-2 | |
| French Open Qual | 05/22 11:55 | 44 | [175] Lorenzo Giustino v Stefano Napolitano [185] | 4-6,4-6 | |
| Challenger - Heilbronn | 05/20 16:50 | 28 | [186] Lorenzo Giustino v Norbert Gombos [100] | 3-6,5-7 | |
| Challenger - Heilbronn | 05/20 10:45 | 27 | [186] Lorenzo Giustino v Andrej Martin [110] | 6-3,7-5 | |
| Challenger - Heilbronn | 05/18 17:30 | 26 | [377] Dominik Koepfer v Lorenzo Giustino [186] | 6-7,6-1,1-6 | |
| Challenger - Heilbronn | 05/16 14:00 | 25 | [174] Dennis Novikov v Lorenzo Giustino [186] | 4-6,4-6 | |
| Challenger - Rome | 05/10 14:00 | 26 | [160] Jozef Kovalik v Lorenzo Giustino [187] | 6-2,6-4 | |
| Challenger - Rome | 05/09 11:35 | 25 | [187] Lorenzo Giustino v Tobias Kamke [149] | 6-3,6-1 | |
| Challenger - Ostrava | 05/02 13:20 | 25 | [208] Stefano Travaglia v Lorenzo Giustino [191] | 6-1,6-3 | |
| Challenger - Francavilla | 04/26 12:00 | 26 | [224] Matteo Donati v Lorenzo Giustino [193] | 6-2,6-7,6-0 | |
| Challenger - Francavilla | 04/24 10:20 | 25 | [241] Igor Sijsling v Lorenzo Giustino [193] | 2-6,1-6 | |
| Challenger - Barletta | 04/15 12:00 | 28 | [97] Gastao Elias v Lorenzo Giustino [214] | 6-4,6-3 | |
| Challenger - Barletta | 04/14 14:20 | 27 | [214] Lorenzo Giustino v Maximilian Marterer [129] | 6-3,6-2 | |
| Challenger - Barletta | 04/12 13:40 | 26 | [214] Lorenzo Giustino v Federico Gaio [164] | 6-3,6-1 | |
| Challenger - Barletta | 04/10 14:20 | 25 | [110] Norbert Gombos v Lorenzo Giustino [214] | 4-6,6-7 | |
| ITF Italy F7 | 04/06 11:55 | 27 | [380] Andrea Collarini v Lorenzo Giustino [214] | 6-4,7-6 | |
| ITF Italy F7 | 04/05 13:30 | 26 | [472] Filippo Baldi v Lorenzo Giustino [214] | 6-3,2-6,4-6 | |
| ITF Italy F7 | 04/04 10:30 | 25 | [466] Andrea Pellegrino v Lorenzo Giustino [214] | 3-6,1-6 | |
| ITF Italy F6 | 04/01 09:00 | 29 | [230] Vaclav Safranek v Lorenzo Giustino [210] | 7-6,6-7,7-5 | |
| ITF Italy F6 | 03/31 09:00 | 28 | [210] Lorenzo Giustino v Stefanos Tsitsipas [204] | 6-3,6-2 | |
| ITF Italy F6 | 03/30 10:20 | 27 | [399] Walter Trusendi v Lorenzo Giustino [210] | 6-7,6-4,1-6 | |
| ITF Italy F6 | 03/29 09:35 | 26 | Luca Prevosto v Lorenzo Giustino | 2-6,3-6 | |
| ITF Italy F6 | 03/27 11:10 | 25 | Alejandro Artunedo v Lorenzo Giustino | 2-6,3-6 | |
| ITF Italy F5 | 03/23 10:40 | 27 | Andrea Basso v Lorenzo Giustino | 3-6,6-4,7-5 | |
| ITF Italy F5 | 03/22 10:15 | 26 | Reda El Amrani v Lorenzo Giustino | 6-3,5-7,4-6 | |
| ITF Italy F5 | 03/21 10:10 | 25 | Francesco Ferrari v Lorenzo Giustino | 5-7,3-6 | |
| ITF Tunisia F9 | 03/11 10:45 | 28 | [216] Lorenzo Giustino v Goncalo Oliveira [422] | 4-6,2-6 | |
| ITF Tunisia F9 | 03/10 09:55 | 27 | Lorenzo Giustino v Cristobal S-Corvalan | 7-5,7-5 | |
| ITF Tunisia F9 | 03/09 08:25 | 26 | Lorenzo Giustino v Mikhail Korovin | 7-5,6-3 | |
| ITF Tunisia F9 | 03/08 08:30 | 25 | Lorenzo Giustino v Cristian Rodriguez | 6-3,6-7,6-0 |
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.