The enormous popularity of Toho's giant monster films led Daiei to issue publicity stills showing the Pairans as gigantic creatures that towered over buildings. In the film, the Pairans are human sized.
This film wasn't released in the United States until 1967.
This was the first color tokusatsu science fiction film produced in Japan. It beat Toho's science fiction spectacle, Ishirô Honda's Chikyû Bôeigun (1957) (the first tokusatsu film in widescreen), into theaters by a year.
The Pairan aliens were designed by the prominent avant-garde artist Taro Okamoto, which used a single eye that is common among science fiction aliens.
The film was one of many early Japanese monster films quickly produced after the success of Toho's Godzilla in 1954. The film was loosely based on a novel by Gentaro Nakajima.
Warning from Space influenced many other Japanese science fiction films, such as Gorath. The film, along with other 1950s science fiction films, influenced director Stanley Kubrick, who would later direct 2001: A Space Odyssey.
Along with other films such as Shintoho's Terrifying Attack of the Flying Saucers and the American Forbidden Planet, Warning from Space became part of a fledgling subgenre of films based around science fiction creatures. The film also used the theme of atomic bombs that was present in many films at the time, but showed how the weapons, which devastated the Japanese cities of Hiroshima and Nagasaki a decade earlier, could be put to good use. It used another common theme of cosmic collisions in the style of earlier films such as the 1931 film End of the World, which depicted a comet on a collision course with the Earth.
Gentaro Nakajima's novel, on which this film was based, was in turn based on the Japanese folktale Kaguya-hime.
Warning From Space was released in Japan on 29 January 1956. Daiei also hoped to find a foreign market for Warning from Space, though the company found difficulty in selling it. Nevertheless, the film played at both King Cinema in Rangoon, Burma and Tai Khoon Theatre in Sandakan, Malaysia, in 1958. The film did help Daiei achieve some success in the genre. It was passed for release, anglicized as Warning from Space, by the BBFC in the United Kingdom in 1957, and later in the United States in 1963. The film was also released as The Mysterious Satellite in some areas. It was shown in the U.S. by American International Television later in the 1960s as Warning From Space. The film was released in Spain as Asalto a la Tierra, and in France as Le Satellite Mystérieux. Warning from Space has since fallen into the public domain, allowing companies to distribute the film for free on DVD.