Flash Gordon Conquers the Universe is a 1940 American black-and-white science-fiction 12-chapter movie serial from Universal Pictures, produced by Henry MacRae and co-directed by Ford Beebe and Ray Taylor. The serial stars Buster Crabbe, Carol Hughes, Charles B. Middleton, Frank Shannon, and Roland Drew. It was written by George H. Plympton, Basil Dickey, and Barry Shipman, and was adapted from Alex Raymond's syndicated newspaper comic strip of the same name from King Features Syndicate. Shown theatrically in 12 separate weekly "chapters", it was the last of the three Universal Flash Gordon serials made between 1936 and 1940.

During the 1950s, all three Flash Gordon serials were syndicated to television by Motion Pictures for Television, along with many of Universal's other serial output. To avoid confusion with the imported Flash Gordon TV series airing around the same time, they were retitled Space Soldiers, Space Soldiers' Trip to Mars, and Space Soldiers Conquer the Universe.

In 1966, Flash Gordon Conquers the Universe was edited down by King Features Syndicate into two feature-length films for television syndication: Purple Death from Outer Space and Perils from the Planet Mongo. In the early 1970s, a third feature version was re-edited for the 16 mm home movie market, using story material taken from the entire serial. It bore the title Space Soldiers Conquer the Universe and later appeared on television during the 1980s. Afterward, all three edited feature-length versions became available through various public-domain video sellers, first on VHS videotape and later on DVD.

In the mid-1970s, all three complete Universal Flash Gordon serials were shown chapter-by-chapter by PBS stations across the U.S., bringing them to a new generation of science-fiction fans, two years before Star Wars and Close Encounters of the Third Kind. From the late 1980s onward, all three serials became available on the home video market under their original theatrical release titles, chapters, and running times.