Prior to 21st century, Oman generally struggled to qualify for the Asian Cup, having been considered as a much weaker side. It was just the rise of Oman national under-17 football team that saw Oman has more opportunity to play in international stage. Eventually, Oman qualified for their first Asian Cup in 2004, before managed to do it again in 2007 and 2015. However, Oman's best performance is just all group stage.
2004 Asian Cup was Oman's first ever participation in continental stage. In here, debutant Oman was placed with Iran, Japan and Thailand. In spite of being considered as a basket point, Oman, however, demonstrated its football feat, and only ended in the group stage with a minor loss to defending champions Japan and a surprising draw to Iran.
Oman qualified for the second consecutive Asian Cup, this time, to meet up again with Thailand, Gulf rival Iraq and debutant Australia. Oman nonetheless impressed by making a stunning 1–1 draw to giant Australia; but a humiliating defeat to host Thailand and another draw with Iraq saw Oman crashed out from group stage for the second times.
Oman would make their third appearance in the tournament, in 2015. Same like 2007, they were placed in Group A again, with Australia, Kuwait and South Korea on board. Oman could not repeat the feat they did to South Korea and Australia before, when Oman lost two opening matches, and crashed out again. A late victory over Kuwait was too little, too late.
1 Considered a successor team by FIFA, or have competed under other name(s). 2 Israel was a member of the AFC until 1974. 3 Recognized by FIFA as defunct.
1956 to 
1980
1984
1988
1992
1996
2000
2004
2007
2015
Iran
Oman
31', 40'
Iraq
Uzbekistan
Turkmenistan