Guilford Dudley (1536 - 12 February, 1554) was a son of John Dudley, Duke of Northumberland, and Jane Guilford; and the younger brother of Robert Dudley, the future earl of Leicester. The unusual first name derives from his mother's family name.

His father was Lord Protector of the kingdom during the reign of King Edward VI of England. On Edward's death, Northumberland feared the accession of the king's sister, the Catholic Mary, and already had a scheme in place to replace her with a Protestant, Lady Jane Grey.

In order to ensure the security of the kingdom against Catholic rule, he had married her to his son Guilford on May 15, 1553.

Within days of the sick boy king Edward's untimely death, Jane was hastily proclaimed queen, and against her own better judgement officially ruled for nine (or thirteen) days, with Guilford as her consort. However, Mary's adherents prevailed; Jane and Guilford were imprisoned, and Guilford, his father and lady Jane were all executed (Jane within the Tower of London, and the accused Dudley family on Tower Hill).

Guilford's unfortunate brothers, John, Ambrose, Robert and Henry , along with their mother, were also for a while incarcerated in the Tower, but were subsequently pardoned.