This novel, perhaps the work for which Plath is most famous, was so autobiographical in nature that the author chose to publish it under a pseudonym. An adolescent girl who grapples with depression and a nervous breakdown, the protagonist was unquestionably based on Plath herself. Describing in often painful detail the trials and indignities of adolescence, punctuated by the main character’s crippling depression, the novel offers lucid portraits of mental illness(and its treatment) as well as the difficulties of being a young woman with feminist leanings.

The Bell Jar has been praised by critics for its dignified, non-pandering treatment of the plight of young women. Charles Newman states that The Bell Jar is "one of the few American novels to treat adolescence from a mature point of view . . . it gives us one of the few sympathetic portraits of what happens to one who has genuinely feminist aspirations in our society, of a girl who refuses to be an 'event' in anyone’s life . . . [Plath] remains among the few woman writers in recent memory to link the grand theme of womanhood with the destiny of modern civilization."

In addition to achieving wide popularity in written form, Plath’s only novel was made into a major motion picture in 1978.