Ou would make his international debut in a friendly match against Canada on 2 April 1992 in a 5–2 defeat. Despite the defeat, Ou would be given the chance to play in several other friendlies which were enough to be called up to the Chinese squad that took part in the 1992 AFC Asian Cup where he played understudy to Fu Yubin. Ou would rise to prominence when he replaced Fu Yubin as the first choice goalkeeper for China in the 1996 AFC Asian Cup by starting the first game of the tournament against Uzbekistan. After a disappointing 1998 FIFA World Cup qualification (AFC), Ou found himself increasingly replaced by Jiang Jin and was replaced as first choice goalkeeper in the 2000 AFC Asian Cup. When China qualified for the FIFA World Cup Jiang Jin remained the first choice goalkeeper throughout the tournament.