Gruffudd ap Owain Glyndŵr (c. 1375 – c. 1412) was the eldest son of Margaret Hanmer and Owain Glyndŵr, who led a major revolt in Wales between 1400 and about 1416.
Gruffudd is recorded as being Owain's eldest son and would-be heir to the crown of Wales had his father's rebellion ultimately been successful in creating an independent Wales.
He is known to have taken part in a raid in south Wales in 1405, alongside his uncle Tudur ap Gruffudd, and another rebel Captain Rhys Gethin.
The result appears to have been a major Welsh defeat, the capture of Gruffudd ab Owain Glyndŵr, and the deaths of Tudur and Rhys Gethin.
He was sent from there to the Tower of London and after seven years died in prison of bubonic plague.