The Gerenia national under-21 football team was the football team for players aged 21 and under which represented the micronation of Gerenia.
The team was founded in early 2016 after the establishment of the Colney Cup as an under-21 tournament, with Gerenia invited to participate in the inaugural edition, where they finished third. In the second edition the following year, the team improved and finished as runners-up. The team was disbanded following the tournament.
Chronological competitive participation
Gerenia under-21 used the following flag during the entirety of its FMF affiliation: