1990–91 Aberdeen F.C. season
Aberdeen F.C. competed in the Scottish Premier Division, Scottish League Cup, Scottish Cup and European Cup Winners' Cup in season 1990–91.
Overview
The 1990-91 season finished on a low note for Aberdeen, as they lost on the final day of the season to Rangers, which gave Rangers the league championship. Aberdeen's defence of the Scottish Cup ended at the first hurdle when eventual winners Motherwell defeated them at Pittodrie in January 1991. In the League Cup, Aberdeen lost to Rangers in the semi final, while in the European Cup Winners' Cup, they lost at the second round stage to Polish club Legia Warsaw. Hans Gillhaus and Eoin Jess finished as joint top scorers with 15 goals each.Results
Scottish Premier Division
Final standings
Scottish League Cup
| Round | Date | Opponent | H/A | Score | Aberdeen Scorer | Attendance |
| R2 | 21 August | Queen's Park | A | 2–1 | Jess, Bett | 2,201 |
| R3 | 29 August | Stranraer | H | 4–0 | Irvine, Van de Ven, Mason | 10,000 |
| QF | 5 September | Heart of Midlothian | H | 3–0 | Van de Ven, Bett, Mason | 15,500 |
| SF | 26 September | Rangers | N | 0–1 | 40,855 |
Scottish Cup
| Round | Date | Opponent | H/A | Score | Aberdeen Scorer | Attendance |
| R3 | 26 January | Motherwell | H | 0–1 | 15,000 |
European Cup Winners' Cup
| Round | Date | Opponent | H/A | Score | Aberdeen Scorer | Attendance |
| R1 L1 | 19 September |  New Salamis | A | 2–0 | Mason, Gillhaus | 7,000 |
| R1 L2 | 3 October | New Salamis | H | 3–0 | Own goal, C. Robertson, Jess | 7,500 |
| R2 L1 | 24 October |  Legia Warsaw | H | 0–0 | 16,000 | |
| R2 L2 | 7 November | Legia Warsaw | A | 0–1 | 5,665 |