| 1991 AFL premiership season | |
|---|---|
| Teams | 15 |
| Premiers | Hawthorn 9th premiership |
| Minor premiers | West Coast 1st minor premiership |
| Pre-season cup | Hawthorn 2nd pre-season cup win |
| Brownlow Medallist | Jim Stynes (Melbourne) |
| Coleman Medallist | Tony Lockett (St Kilda) |
| Attendance | |
| Matches played | 172 |
| Total attendance | 4,178,884 (24,296 per match) |
| Highest | 75,230 (Grand Final, Hawthorn vs. West Coast) |
The 1991 AFL season was the 95th season of the Australian Football League (AFL), which was known previously as the Victorian Football League until 1989. The season ran from 22 March until 28 September, and comprised a 22-game home-and-away season followed by a finals series featuring the top six clubs, an increase from the top five clubs which had contested the finals since 1972.
The season saw expansion of the league to fifteen clubs, with the admission of the newly established Adelaide Crows, based in Adelaide, South Australia. With at least one team representing each of the three major Australian rules football states, the league was now the highest level senior Australian rules football competition across Australia, as well as the top administrative body for football in Victoria.
The premiership was won by the Hawthorn Football Club for the ninth time, after defeating West Coast by 53 points in the 1991 AFL Grand Final.