| Competition: | AFLU |
| Year: | 1991 |
| Date: | 23 March – September |
| Teams: | 12 |
| Count: | 7 |
| Prevseason: | 1990 |
| Nextseason: | 1992 (TAC Cup) |
The 1991 AFL under-19s season was the 45th and final season of the AFL under-19s competition, the Australian rules football competition operating as the junior competition to the Australian Football League (AFL).
won their 7th under-19s premiership and their second in a row, defeating by 38 points at VFL Park.
At the end of the season, the under-19s was disbanded and a new competition − called the TAC Cup − began in 1992 with teams that were not linked to AFL clubs.[1]
| Team | ||||||||
| 1 | 22 | 17 | 5 | 0 | 179.6 | 68 | ||
| 2 | (P) | 22 | 16 | 6 | 0 | 154.1 | 64 | |
| 3 | 22 | 16 | 6 | 0 | 153.3 | 64 | ||
| 4 | 22 | 14 | 7 | 1 | 118.9 | 58 | ||
| 5 | 22 | 13 | 8 | 1 | 125.7 | 54 | ||
| 6 | 22 | 13 | 9 | 0 | 118.7 | 52 | ||
| 7 | 22 | 12 | 10 | 0 | 120.5 | 48 | ||
| 8 | 22 | 10 | 12 | 0 | 68.9 | 40 | ||
| 9 | 22 | 6 | 16 | 0 | 75.1 | 24 | ||
| 10 | 22 | 6 | 16 | 0 | 55.9 | 24 | ||
| 11 | 22 | 5 | 17 | 0 | 69.6 | 20 | ||
| 12 | 22 | 3 | 19 | 0 | 52.6 | 12 |