Mothra vs. Godzilla (モスラ対ゴジラ, Mosura tai Gojira) is a 1964 Japanese kaiju film directed by Ishirō Honda, with special effects by Eiji Tsuburaya. Produced and distributed by Toho Studios, it is the fourth film in the Godzilla franchise. The film stars Akira Takarada, Yuriko Hoshi, Hiroshi Koizumi, Kenji Sahara, and the Peanuts, with Haruo Nakajima as Godzilla. In the film, humans beseech the aide of the insect-god Mothra to stop Godzilla from destroying Japan.

Due to the success of King Kong vs. Godzilla (1962), Toho chose to pair Godzilla against Mothra for the following film, with Mothra chosen due to the success of Mothra (1961). Honda directly intended for the film to be meant for children in addition to adults, as a way to compete with television's growing popularity in Japan. Notably, it is the final film in the franchise's Shōwa period to depict Godzilla solely as an antagonist.[7]

Mothra vs. Godzilla was released theatrically in Japan on April 29, 1964.[2][8] An edited version titled Godzilla vs. the Thing was released by American International Pictures in the United States on August 26, 1964. The film was followed by Ghidorah, the Three-Headed Monster, released in the same year on December 20.