Isabelle Stever was born in Munich in 1963 and grew up in Munich, Paris and North Rhine-Westphalia. In 1984 she moved to Berlin, where she initially studied mathematics. During this time she worked part-time in the film business. After graduating in 1994, she successfully applied to the German Film and Television Academy Berlin (DFFB). For her feature-length graduation film "Erste Ehe" (2002), she received the First Steps Award for Best Feature Film; at the Max Ophüls Preis Film Festival, Maria Simon was named Best Newcomer. Stever's second feature film, the love triangle "Gisela," set in a precarious environment, premiered at the Munich Film Festival in 2005, but did not receive a theatrical release; instead, it was broadcast on television after having toured other festivals.

In 2008, she contributed an episode to the project "Deutschland '09 - 13 kurze Filme zur Lage der Nation" (Germany '09 - 13 Short Films on the State of the Nation), whose other directors included Dani Levy, Angela Schanelec, Dominik Graf and Nicolette Krebitz. The premiere took place in the competition of the Berlinale 2009, where the film was shown out of competition. Stever's third feature film, the love story "Glückliche Fügung" (2010), also screened at several international festivals and was released in German cinemas in early 2011. At the 2015 Zurich Film Festival, Stever presented the drama "Wetter in geschlossenen Räumen," a film about a burned-out aid worker who begins a momentous affair with a young drifter. At the 2morrow Film Festival in Moscow, lead actress Maria Furtwängler won the Best Performance award and Stever won the Best Story award. The film was released in early 2016.

In fall 2020 filming took place for Isabelle Stever's next project, "Grand Jeté", a psychological mother-son story. In 2021, Stever was a fellow at Villa Aurora in Los Angeles. In February 2022, "Grand Jeté" had its world premiere in the Panorama of the 2022 Berlinale; it was released the following August.

In addition to her work as a director and screenwriter, Isabelle Stever is a lecturer at the DFFB and the Filmakademie Baden-Württemberg.