The 1990–91 Welsh Cup winners were Swansea City. The final was played at the National Stadium in Cardiff in front of an attendance of 5,000.

Fourth round edit

Tie no Home team Score Away team
1 Aberystwyth Town 1–3 Hereford United
2 Ammanford Town F.C. 0–5 Wrexham
3 B.P Llandarcy 0–5 Stroud
4 Bangor City 4–1 Lex XI
5 Caernarfon Town 1–2 Abergavenny Thursdays
6 Barry Town 3–1 Cheltenham Town
7 Merthyr Tydfil 0–1 Swansea City
8 Newport 0–1 Colwyn Bay

Quarter-finals edit

Tie no Home team Score Away team
1 Barry Town 1–1 Bangor City
Replay Bangor City 0–1 Barry Town
2 Colwyn Bay 1–1 Swansea City
Replay Swansea City 1–0 Colwyn Bay
3 Bangor City 0–0 Hereford United
Replay Hereford United 0–0 Bangor City
Hereford win 4–3 on penalties
4 Stroud 1–2 Wrexham

Semi-finals – 1st leg edit

Tie no Home team Score Away team
1 Barry Town 2–2 Swansea City
2 Wrexham 1–1 Hereford United

Semi-finals – 2nd leg edit

Tie no Home team Score Away team
1 Swansea City 1–0 Barry Town
2 Hereford United 1–2 Wrexham

Final edit

Swansea City2–0Wrexham
Penney  
Raynor  
Attendance: 5,000
Referee: K Burge (South Wales)
 
 
 
 
 
 
 
Swansea City
 
 
 
 
 
 
 
Wrexham