1986 King Cup
The 1986 King Cup was the 28th season of the knockout competition since its establishment in 1956. Al-Ettifaq were the defending champions but they were eliminated by Al-Tai in the quarter-finals.
Al-Nassr won their 4th title after defeating Al-Ittihad 1–0 in the final. This was their first title since 1981.
Bracket
Note: H: Home team, A: Away teamSource:
Round of 16
The matches of the Round of 16 were held on 6 and 7 January 1986.| Home team | Score | Away team |
| Al-Ettifaq | 4–0 | Al-Arabi |
| Al-Kawkab | 1–7 | Al-Riyadh |
| Al-Nassr | 2–0 | Al-Wehda |
| Al-Wadea | 1–0 | Al-Nahda |
| Al-Ittihad | 2–1 | Al-Ansar |
| Al-Ahli | 1–2 | Al-Tai |
| Al-Hilal | 1–1 | Al-Qadsiah |
| Al-Shoulla | 1–1 | Al-Shabab |
Quarter-finals
The Quarter-final matches were held on 10 January 1986.| Home team | Score | Away team |
| Al-Tai | 2–1 | Al-Ettifaq |
| Al-Riyadh | 2–3 | Al-Nassr |
| Al-Qadsiah | 2–0 | Al-Wadea |
| Al-Shabab | 1–1 | Al-Ittihad |