1937–38 Welsh Cup
The 1937–38 FAW Welsh Cup is the 57th season of the annual knockout tournament for competitive football teams in Wales.
Key
League name pointed after clubs name.- B&DL - Birmingham & District League
- CCL - Cheshire County League
- FL D2 - Football League Second Division
- FL D3N - Football League Third Division North
- FL D3S - Football League Third Division South
- MWL - Mid-Wales Football League
- ML - Midland League
- SFL - Southern Football League
- WLN - Welsh League North
- WLS D1 - Welsh League South Division One
- WCL - West Cheshire League
- W&DL - Wrexham & District Amateur League
Second round
20 winners from the first round plus Haverfordwest Athletic and Lovell's Athletic.| Tie no | Home | Score | Away |
| 1 | Blaenau Ffestiniog | 1–1 | Penrhyn Quarry |
| replay | Penrhyn Quarry | 4–1 | Blaenau Ffestiniog |
| 2 | Courtaulds Holywell | 3–1 | Buckley Town |
| 3 | Chirk | 2–1 | Gwersyllt |
| 4 | Llay Welfare | 3–0 | Cross Street Gwersyllt |
| 5 | Castle Firebrick Works | 3–5* | Caergwrle |
| replay | Castle Firebrick Works | 0–0 | Caergwrle |
| replay | Caergwrle | 2–1 | Castle Firebrick Works |
| 6 | Porthmadog | 7–1 | Dolgelley Albion |
| 7 | Aberystwyth Town | 5–4 | Aberdovey |
| 8 | Llanidloes Town | 7–1 | Welshpool |
| 9 | Haverfordwest Athletic | 3–1 | Tredomen Works |
| 10 | Lovell's Athletic | 4–1 | Caerphilly United |
| 11 | Ebbw Vale | 3–8 | Llanelly |
Third round
10 winners from the second round plus 14 new clubs. Llanelly get a bye to the fourth round.| Tie no | Home | Score | Away |
| 1 | Penrhyn Quarry | 5–4 | Porthmadog |
| 2 | Macclesfield | 3–1 | Bangor City |
| 3 | Kidderminster Harriers | 1–2 | Cheltenham Town |
| 4 | Wellington Town | 6–0 | Hereford United |
| 5 | Oswestry Town | 1–1 | Shrewsbury Town |
| replay | Shrewsbury Town | 6–3 | Oswestry Town |
| 6 | Caergwrle | 4–3 | Llay Welfare |
| 7 | Chirk | 3–2 | Courtaulds Holywell |
| 8 | Aberystwyth Town | 0–1 | Llanidloes Town |
| 9 | Aberdare Town | 0–3 | Aberaman |
| 10 | Cardiff Corinthians | 2–3 | Gwynfi Welfare |
| 11 | Lovell's Athletic | 3–0 | Milford United |
| 12 | Haverfordwest Athletic | 4–4 | Troedyrhiw |
| replay | Troedyrhiw | 1–2 | Haverfordwest Athletic |
Fourth round
12 winners from the third round, Llanelly and one new team - Worcester City.| Tie no | Home | Score | Away |
| 1 | Wellington Town | 1–3 | Cheltenham Town |
| 2 | Macclesfield | 0–7 | Shrewsbury Town |
| 3 | Llanidloes Town | 4–1 | Chirk |
| 4 | Penrhyn Quarry | 0–0* | Caergwrle |
| 5 | Llanelly | 2–1 | Haverfordwest Athletic |
| 6 | Aberaman | 1–2 | Worcester City |
| 7 | Gwynfi Welfare | 0–3 | Lovell's Athletic |
Fifth round
Four winners from the fourth round. Cheltenham Town, Shrewsbury Town and Worcester City get a bye to the Sixth round.| Tie no | Home | Score | Away |
| 1 | Llanidloes Town | 2–1 | Caergwrle |
| 2 | Llanelly | 3–0 | Lovell's Athletic |
Sixth round
Two winners from the fifth round, Cheltenham Town, Shrewsbury Town and Worcester City and eleven new clubs.| Tie no | Home | Score | Away |
| 1 | Newport County | 6–2 | Bristol City |
| 2 | Worcester City | 2–2 | Barry |
| replay | Barry | 1–1 | Worcester City |
| replay | Worcester City | 2–0 | Barry |
| 3 | Swansea Town | 8–0 | Llanelly |
| 4 | Cardiff City | 0–1 | Cheltenham Town |
| 5 | New Brighton | 1–5 | Chester |
| 6 | Llanidloes Town | 1–1 | Rhyl |
| replay | Rhyl | 1–0 | Llanidloes Town |
| 7 | Wrexham | 1–3 | Shrewsbury Town |
| 8 | Southport | 2–0 | Crewe Alexandra |
Semifinal
Swansea Town and Rhyl played at Chester.| Tie no | Home | Score | Away |
| 1 | Shrewsbury Town | 3–2 | Newport County |
| 2 | Swansea Town | 7–2 | Rhyl |
Final
Both final and replay were held in Shrewsbury.| Tie no | Home | Score | Away |
| 1 | Shrewsbury Town | 2–2 | Swansea Town |
| replay | Shrewsbury Town | 2–1 | Swansea Town |