The 1990 King Cup was the 32nd season of the knockout competition since its establishment in 1956. Al-Hilal were the defending champions but they were eliminated by Al-Riyadh in the Round of 16. This season was the final season of the competition. the Cup then returned under the name of King Cup of Champions in 2008.
Al-Nassr won their 6th title after defeating Al-Taawoun 2âÂÂ0 in the final. By reaching the final Al-Taawoun became the second First Division side to reach the final after Al-Riyadh in 1978. As winners of the tournament, Al-Nassr qualified for both the 1991 Arab Cup Winners' Cup and the 1991âÂÂ92 Asian Cup Winners' Cup.
Note: H: Home team, A: Away team
The matches of the Round of 16 were held on 3 and 4 May 1990.
The matches of the Quarter-finals were held on 10 and 11 May 1990.
The four winners of the quarter-finals progressed to the semi-finals. The semi-finals were played on 17 and 18 May 1990. All times are local, AST ().
The final was played between Al-Nassr and Al-Taawoun in the Youth Welfare Stadium in Jeddah. Al-Nassr were appearing in their 10th final while Al-Taawoun reached the final for the first time.