Sir Roger Clarendon (c.1350–1402), was a royal bastard and conspirator, who was executed for treason.
Clarendon was a natural son of Edward the Black Prince, and his mistress, Edith Willesford. He was a paternal half-brother to Richard II of England. Being regarded as a possible pretender, Clarendon was hanged and beheaded by order of Henry IV of England in 1402. His execution was made the subject of one of the articles exhibited by Richard Scrope, Archbishop of York, against Henry IV during a rebellion in 1405.