Question: what episode in grey's anatomy does izzy die

title: Izzie Stevens
text: Izzie makes a treatment error that endangers the life of a patient , and is fired from the hospital 's surgical program . Believing Alex is partially to blame , she writes him a Dear John letter and leaves . Izzie later learns that Alex was not responsible for her lost job , and returns to make amends with him , but Meredith informs her that Alex is moving on . Izzie informs Alex that she no longer has cancer . Although he is pleased , Alex officially breaks up with Izzie , telling her that he loves her but deserves better . She leaves Seattle to start fresh . Several episodes later , Alex informs Meredith that Izzie sent divorce papers , which he signs in the episode `` How Insensitive '' . In the sixth - season finale , Alex is shot and asks for Izzie . Imagining that Meredith 's half - sister Lexie ( Chyler Leigh ) is Izzie , he apologizes and asks her never to leave him again .