William Morgan (died 1649) was a Welsh lawyer and politician who sat in the House of Commons from 1640 to 1649.
Morgan was the son of Llewellyn Morgan of Ystradfellte. He was called to the bar. He purchased the estate of Dderw in Llyswen. He was recorder of Brecon from 1637 and was King's attorney in South Wales until his death.
In April 1640, Morgan was elected Member of Parliament for Breconshire in the Short Parliament. He was re-elected MP for Breconshire for the Long Parliament in November 1640 and sat until his death in 1649. In February 1649 information was laid against him that he had supported the Royalist cause in the Civil War, raising money and arms for the king and sitting in the King's parliament in Oxford.
Morgan died in 1649 and was buried in the Priory Church, Brecon.
Morgan married Elizabeth Morgan, daughter of Sir William Morgan of Tredegar. His son William was High Sheriff in 1655. He was the father-in-law of William Morgan (of Machen and Tredegar).