Oulujoki (in modern Finnish literally "Oulu River", originally in old Northern Ostrobothnian dialect literally "Flood River", ) is a river in Oulu province, Finland. Its origin is Oulujärvi and its watershed area covers a significant part of Kainuu region. It flows into the Bothnian Bay at Oulu. Port of Oulu is located at the mouth of the river.

Oulujoki (in modern Finnish literally "Oulu River", originally in old Northern Ostrobothnian dialect literally "Flood River", ) is a river in Oulu province, Finland. Its origin is Oulujärvi and its watershed area covers a significant part of Kainuu region. It flows into the Bothnian Bay at Oulu. Port of Oulu is located at the mouth of the river.