US version removes a scene explaining connection to preceding film.
Much of Akira Ifukube's score is replaced with several generic themes from American B-pictures.
In the original version, the search of the ship Gaira attacked took place before the maritime authorities contacted Doctor Stewart while the American version it not only took part after Stewart was contacted, he is seen on the search vessel questioning the divers.
In the original version both Sanda and Gaira are referred to by their names throughout the film. However, in the American version they are only referred to as brown and green Gargantua respectively.
In the original version, Dr. Stewart (played by Russ Tamblyn) was not present in the scene where the sole survivor of Gaira's first attack is questioned. However, in the American version he is seen in the room observing as the maritime authorities question the man.
In the Japanese version there are no sound effects when the Gargantuas take a step. However, in the American version you hear a stomping sound whenever the monsters are walking or running.
Italy's reissue version released in the 70's as Kong, uragano sulla metropoli, has strange sound effects every time that Gaira appears on screen. This version appears on italian DVD as Katango uragano sulla metropoli where Katango is the first release title.
The Paramount tape restores the scene referencing Furankenshutain's severed hand from the previous film.