1988 King Cup
The 1988 King Cup was the 30th season of the knockout competition since its establishment in 1956. Al-Nassr were the defending champions but they were eliminated by eventual champions Al-Ittihad in the semi-finals.
Al-Ittihad won their 6th title after defeating Al-Ettifaq 1–0 in the final. This was the first final to be held in the King Fahd International Stadium. As winners of the tournament, Al-Ittihad qualified for the 1989 Arab Cup Winners' Cup.
Round of 16
Both Al-Ettifaq and Ohod received a bye to the next round. Al-Ettifaq received due to their participation in the 1988 Gulf Club Champions Cup. Ohod received a bye to the lack of teams participating in this round. The matches of the Round of 16 were held on 31 March and 1 April 1988.| Home team | Score | Away team |
| Al-Ettifaq | Bye | |
| Ohod | Bye | |
| Al-Ahli | 3–3 | Al-Riyadh |
| Al-Ittihad | 1–0 | Al-Qadsiah |
| Al-Tai | 0–1 | Al-Nahda |
| Al-Kawkab | 0–2 | Al-Wehda |
| Al-Tuhami | 2–2 | Al-Shabab |
| Al-Nassr | 1–0 | Al-Hilal |
Quarter-finals
The matches of the Quarter-finals were held on 7 and 8 April 1988.| Home team | Score | Away team |
| Al-Nassr | 4–0 | Ohod |
| Al-Riyadh | 1–3 | Al-Shabab |
| Al-Ettifaq | 1–0 | Al-Wehda |
| Al-Nahda | 0–4 | Al-Ittihad |