The 1986-87 Welsh Cup winners were Merthyr Tydfil. The final and replay were played at Ninian Park in Cardiff in front of attendances of 7,000 and 6,010 respectively.

Semi-finals – first leg

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Tie no Home team Score Away team
1 Newport County 2–1 Wrexham
2 Merthyr Tydfil 1–0 Bangor City

Semi-finals – second leg

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Tie no Home team Score Away team
1 Wrexham 2–2 Newport County
2 Bangor City 1–0 (2−4p) Merthyr Tydfil

Final

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Merthyr Tydfil2–2Newport County
Latchford  
Webley  
Thackeray 2  
Attendance: 7,000
Referee: F Roberts (Prestatyn)
 
 
 
 
 
Merthyr Tydfil
 
 
 
 
 
Newport County

Replay

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Merthyr Tydfil1–0Newport County
Baird  
Attendance: 6,010
Referee: F Roberts (Prestatyn)
 
 
 
 
 
Merthyr Tydfil
 
 
 
 
 
Newport County
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