U21-EM - Kval 09/04 14:00 1 Italia U21 v San Marino U21 - View
U21-EM - Kval 09/09 14:00 1 San Marino U21 v Tyrkia U21 - View
U21-EM - Kval 10/14 14:00 1 San Marino U21 v Latvia U21 - View

The San Marino national under-21 football team represents the under-21s of San Marino in the UEFA U-21 Championship, and is controlled by the San Marino Football Federation (FSGC, Italian: Federazione Sammarinese Giuoco Calcio), the governing body of football of the state.

San Marino national under-21 football team competed for the first time in the qualifications for the 1990 UEFA European Under-21 Football Championship. Since then they missed two qualifying tournaments (2000 and 2002). Until 2015 qualifying they won only two matches, both by forfeit. In the 2004 qualifying they lost 6–0 to Sweden but UEFA later awarded the match as a 3–0 forfeit win to San Marino due to Sweden including suspended players in their squad. In the preliminary round of the 2007 qualifying they lost 2–1 to Armenia but UEFA also awarded the match as a 3–0 forfeit win for San Marino. In June 2012, they held Greece to a goalless draw in the 2013 qualifying. On 6 September 2013, San Marino recorded their first competitive win 1–0 over Wales at Stadio Olimpico in the 2015 qualifying. This was also the first competitive victory of any San Marino national team since a 2–1 under-17 victory against Andorra in 2002.

San Marino U21 er det sanmarinske U21-landslaget i fotball for herrer. Laget representerer San Marino i internasjonale konkurranser for U21-landslag, og kontrolleres av San Marinos fotballforbund.

San Marino U21 har aldri kvalifisert seg til et U21-EM. Deres største bragd er en uavgjort 1-1 mot Tyrkia i kvalifiseringen til U21-EM i 2017.