Peter Fleischmann, born July 26, 1937, in Zweibrücken, studied at Deutsches Institut für Film und Fernsehen (DIFF) in Munich and subsequently worked as an assistant director and unit manager for the production company Schongerfilm. From 1960 to 1962, Fleischmann studied at Institut des Hautes Etudes Cinématographiques (IDHEC) in Paris. After his graduation, he directed several children's and short documentary films. His short children"s film "Alexander und das Auto ohne linken Scheinwerfer" won a special award at the 1966 Venice film festival.

With his first full-length documentary film, Fleischmann already made a name as a critically inconvenient filmmaker: "Der Herbst der Gammler" depicts the conflicts between young and old Munich citizens. One year later, Fleischmann made his first full-length feature film, "Jagdszenen aus Niederbayern" ("Hunting Scenes from Bavaria"). Based on Martin Sperr's folk play, the film tells the story of the "everyday fascism" (CineGraph) of German provinces. A young man (played by Sperr himself) is ridiculed and excluded from the village community for his homosexual orientation and driven to an act of desperation.

In 1969, "Jagdszenen aus Niederbayern" won a "Filmband in Silber" at the German film awards. In the same year, Fleischmann founded the production company "Hallelujah Film" together with Volker Schlöndorff. Fleischmann's next films, the bourgeois drama "Das Unheil" ("Havoc"), based on a screen play by Martin Walser, and, most notably, the "anti porn movie" (Fleischmann) "Dorotheas Rache" ("Dorothea's Revenge") caused strong controversies. "Dorotheas Rache", a film about a young woman who voluntarily works as a prostitute, was at first confiscated in Bavaria but eventually got released later on. "Der 3. Grad", a film about live in a police state, the allegorical political drama "Die Hamburger Krankheit" ("The Hamburg Syndrome"), and the now turned cult-classic science fiction film "Es ist nicht leicht ein Gott zu sein" ("Hard To Be a God") further consolidated Fleischmann's image as one of German cinema's most unconventional and socio-critical auteur filmmakers. During the 1990s, he was a board member of Babelsberg Studios in Potsdam lead by Volker Schlöndorff.

After a long period in which he didn't release any films, Fleischmann returned to the screen in 2006 with his long-term portray of Bernhard Kimmel in "Mein Freund der Mörder". However, this was to remain his last film. On August 11, 2021, Peter Fleischmann, who had last lived in Werder near Potsdam, died as a result of a serious fall.