Michael Graham Cox (6 January 1938 – 8 April 1995) was an English actor.

He was most famous for voicing Boromir in the 1978 film The Lord of the Rings, as well as voicing Boromir in the 1981 BBC radio series The Lord of the Rings. He also voiced Bigwig in the feature film Watership Down.

Cox had a minor role in Richard Attenborough's A Bridge Too Far and Cry Freedom. He appeared many times on stage and in television dramas such as Grange Hill, as kindly teacher Mr. Butterworth. He also starred with Derek Nimmo and Rosemary Leach in the TV sitcom Life Begins At Forty. Other BBC radio dramas produced and directed by Jane Morgan (a lifelong, friend and colleague) included her Dickens series.

Cox is survived by his first wife Davina Beswick, a student from the Bristol Old Vic, and their son Dominic.