The 1921 VJFL season was the 3rd season of the Victorian Junior Football League (VJFL), the Australian rules football competition operating as the second-tier competition to the Victorian Football League (VFL). The home-and-away season began on 7 May and ended on 17 September.
won its first premiership in its first season, defeating reigning premiers .
In addition to Essendon Juniors, joined the VJFL in 1921, replacing and (the junior team of ). Coburg had been playing in the Melbourne District Football Association and won three premierships in that competition, the most recent in 1920.