Garry Chalk (born February 17, 1952) is a British-born Canadian actor, dual US-Canadian citizen and voice artist. Also known as Garry Chalk, he is best known for being among the voices of Optimus Primal in the Transformers universe and has appeared in The Fly II, Freddy vs. Jason, Deck the Halls, Watchmen and Scooby-Doo! The Mystery Begins. Chalk was born in Southampton, Hampshire in 1952. At the age of 5, his family moved to Vancouver, British Columbia, Canada.

Chalk has been involved with theatre since 1978 and has performed at the Vancouver Playhouse Theatre Company (VPTC), the Arts Club Theatre Company (ACTC), The Vancouver Theatresports League and various low budget theatres in Canada. The last live stage production he did was A Funny Thing Happened on the Way to the Forum, where he played Miles Gloriosus. He also performed in Henry IV and As You Like It at the VPTC, as well as Dracula and Passion at the ACTC.

Most of his career has been in film and television, usually portraying corrupt members of law enforcement. He had a recurring role on Cold Squad for four years, for which he won Gemini Awards in two consecutive years, and until the close of its ninth season had a recurring role on the science-fiction series Stargate SG-1. Known for his perfect enunciation and his mellifluous deep voice, Chalk is also a veteran of over 1,500 animated productions including Class of the Titans, and the 2002 remake of He-Man and the Masters of the Universe. He is also known for his voice work in the Transformers franchise as the voice of Optimus Primal in Beast Wars and Beast Machines, and as Optimus Prime in the Unicron Trilogy. He also voiced the original Megatron in an episode of Beast Wars.

In the 2000s, he appeared in the Sci-Fi Channel shows Eureka, as Col. Briggs and Painkiller Jane, as Ruben Hennessey.