The Death Ray (Russian: Луч смерти, romanized: Luch smerti) is a 1925 Soviet science fiction film directed by Lev Kuleshov. The first and last reels of the film have been lost. This film ran at 2 hours, 5 minutes, making this one of the earliest full length science fiction films.

Despite the fact that many sources claim the inspiration for the film to be the novel The Garin Death Ray by Aleksei Tolstoy, this is not the case. It is impossible, since the book was published two years after the film, in 1927. Furthermore, the film has many similarities with a book by Valentin Kataev, called Lord of Iron, published in 1924. Moreover, the theme of death rays was very popular at the time because of the 1923 claim of British inventor Harry Grindell Matthews to have created a "death ray".