Director Timo Vuorensola's movie sees an America led by President Sarah Palin fighting off an invasion from exiled Nazis attacking from the dark side of the moon.
Vuorensola admitted that the project, which has been six years in the making with a budget of €7.5 million, was "extremely difficult".
"The many hardships and all the trouble we went through to make an indie product like this was staggering, but we pulled it through," he said. "We're proud of our accomplishments, and the theatrical trailer gives a powerful glimpse into the world of Iron Sky."
Iron Sky has already amassed a significant online following, with the film's Facebook page having 100,000 fans.
Christopher Kirby, Julia Dietze, Götz Otto, Peta Sergeant, Udo Kier and Stephanie Paul star in Iron Sky, which has an April 4 release date.
> Iron Sky: Bad Moon Rising comic miniseries announced