Luke Gernon (c.1580 – c.1672) was an Irish judge who held office in seventeenth-century Ireland. He is best remembered today for his manuscript (which seems to have been a private letter) called A Discourse of Ireland. The Discourse was written in 1620, and was first published in 1904.
He had several notable descendants, including his grandson, the poet Nicholas Brady, and Maziere Brady, a long-serving Lord Chancellor of Ireland in the nineteenth century.