He is best known for his documentary Mein Kampf, based on Nazi footage from secret archives and depicting Nazi atrocities. He subsequently made other documentaries both on Nazi Germany and other topics.
In 1967, he was a member of the jury at the Venice Film Festival.
Leiser published the book Nazi Cinema in 1974.
Erwin Leiser was buried in Zürich's Israelitischer Friedhof Oberer Friesenberg.