| Ferdinando La Manna | ITA | 2016/17 | 2 | 2 | 0 | 0 | 6 | 0 | Carpi U19 | | |
| Enrico Lanzi | ITA | 1987/88 | 1 | 1 | 0 | 0 | 2 | 0 | Pavia U19 | | |
| Rino Lavezzini | ITA | 2003/04 | 4 | 1 | 3 | 0 | 5 | 1 | Livorno U19, Genoa U19 | | |
| Dario Lazzarin | ITA | 2006/07 | 2 | 2 | 0 | 0 | 10 | 0 | Chievo Verona U19 | | |
| Nunzio Lazzaro | ITA | 2023/24 | 0 | 0 | 0 | 0 | 0 | 0 | Borgaro Nobis | | |
| Christian Legovich | USA | 2010/11 | 1 | 1 | 0 | 0 | 5 | 1 | LIAC New York U19 | | |
| Nicola Legrottaglie | ITA | 2019/20 | 1 | 0 | 0 | 1 | 1 | 3 | Pescara U19 |  | |
| Jerko Leko | CRO | 2025/26 | 0 | 0 | 0 | 0 | 0 | 0 | Dinamo Zagreb U19 | | |
| Attilio Lombardo | ITA | 2005/06 | 5 | 4 | 1 | 0 | 15 | 5 | Manchester City U19, Sampdoria U19 | | |
| Moreno Longo | ITA | 2012/13 | 13 | 8 | 2 | 3 | 18 | 12 | Torino U19 | | |
| Pasquale Loseto | ITA | 1990/91 | 2 | 0 | 1 | 1 | 1 | 2 | Bari U19 | | |
| Stefano Lucchini | ITA | 2019/20 | 1 | 1 | 0 | 0 | 3 | 0 | Cremonese U19 | | |
| Luna | MES | 1993/94 | 1 | 1 | 0 | 0 | 2 | 1 | Pumas UNAM U20 | | |
| Alessandro Lupi | ITA | 2017/18 | 4 | 1 | 2 | 1 | 7 | 8 | Milan U19, Monza U19, Sampdoria U19 | | |
| Agustín López | SPA | 2015/16 | 4 | 2 | 0 | 2 | 4 | 3 | Sevilla U19 | | |
| Diego López | URU | 2012/13 | 1 | 0 | 0 | 1 | 0 | 5 | Cagliari U19 | | |
| Julián López de Lerma | SPA | 2025/26 | 1 | 0 | 0 | 1 | 0 | 1 | Real Madrid U19 | | |
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