Deio ab Ieuan Du

Deio ab Ieuan Du (fl. 1460–1480) was a Welsh language poet from Ceredigion, west Wales.

Deio composed eulogies to the nobility of the area, including Gruffydd Fychan, a supporter of Jasper Tudor.

His works were edited in 1992 by A. Eleri Davies along with those of Gwilym ab Ieuan Hen.