Haruo Nakajima (born January 1, 1929 in Yamagata, Japan) is a Japanese actor and stunt performer best known for appearing in various Akira Kurosawa films and for playing the title character in various Godzilla films from it's incarnation in the early '50s to early '70s.
He portrayed the giant atomic-breathing mutated kaiju (Japanese for monster) in Gojira, Godzilla Raids Again, King Kong vs. Godzilla, Godzilla vs. Mothra, Ghidorah, the Three-Headed Monster, Godzilla vs. the Sea Monster (A.K.A. Ebirah, Horror of the Deep), Son of Godzilla, Destroy All Monsters, Godzilla's Revenge, Godzilla vs. the Smog Monster (in which he also played a few other background civilian characters) and Godzilla vs. Gigan. Stock footage of his other appearances was used in Godzilla vs. Megalon; due to that questionable edit, Joel Robinson and the SOL crew end up riffing that they've seen this already.
He portrayed other kaiju creations in films such as Rodan, Varan, The Mysterians, The Human Vapor, Mothra, Gorath, Matango, Frankenstein Conquers the World, Invasion of Astro Monster, The War of the Gargantuas, King Kong Escapes, Latitude Zero and Yog: Monster from Space.