This article is about the cycle of poems by James Macpherson and their main character. For the character from Irish mythology, see Oisín. For other uses of the name Ossian, see Ossian (disambiguation).

Ossian is the narrator, and supposed author, of a cycle of poems which the Scottish poet James Macpherson claimed to have translated from ancient sources in the Scots Gaelic. The furore over the "authenticity" of the poems has continued to the present. Ossian is based on Oisín, son of Fionn mac Cumhail, a character from Irish mythology.