Born in Paris, Pierre Klossowski was the older brother of the artist Balthazar Klossowski, better known as Balthus. Their parents were the art historian Erich Klossowski and the painter Baladine Klossowska. His father, Erich Klossowski, was a German-educated Polish noble of the Rola coat of arms. His mother, Baladine Klossowska, was born as Elisabeth Dorothea Spiro in Breslau, Prussia (now Wroc?aw, Poland). Although the family has denied any Jewish heritage, a Polish journal reported Baladine was born into an Orthodox Jewish family with Belarussian origins.

When he was 18, Pierre was André Gide's secretary and worked on the drafts of Les faux-monnayeurs for him.

Pierre Klossowski wrote full length volumes on the Marquis de Sade and Friedrich Nietzsche, a number of essays on literary and philosophical figures, and five novels. He translated several important texts (by Virgil, Ludwig Wittgenstein, Martin Heidegger, Friedrich Hölderlin, Franz Kafka, Nietzsche, and Walter Benjamin) into French, worked on films and was also an artist, illustrating many of the scenes from his novels. Klossowski participated in most issues of George Bataille's review, Acéphale, in the late 1930s.

His 1969 book, Nietzsche and the Vicious Circle, greatly influenced French philosophers such as Michel Foucault, Gilles Deleuze, and Jean-François Lyotard.

Klossowski also appeared in Robert Bresson's Au hasard Balthazar as the avaricious miller who desires Marie, a character played by Anne Wiazemsky.

He was involved in :

- Raoul Ruiz's La vocation suspendue, 1977, 90' ;

- Raoul Ruiz's L'hypothèse du tableau volé, 1979, 66' ;

- Pierre Zucca's Roberte, 1979, 100' ;

- Alain Fleischer's Pierre Klossowski ou l'éternel détour, 1996, 106'.

His text on de Sade is mentioned in the bibliography at the beginning of Pier Paolo Pasolini's Salò, or the 120 Days of Sodom, and quoted several times through the film.

From 20 September to 19 October 2006 there was a display of Klossowski's drawings and life size sculptures made after them with sculptor Jean-Paul Réti along with the art of Hans Bellmer at the Whitechapel Art Gallery also presented at the Ludwig Museum in Cologne and the Musée National d'Art Moderne in Paris with a film retrospective.