In her essay, "On Being Ill"(1931), Virginia Woolf observes that illness discloses the "undiscovered countries" in our minds with the police of reason "off duty." Like an explorer of the unknown territories, in her writing she investigates the uncharted parts of her mind that are opened by illness. Woolf made an interesting analogy between her experiences of illness and her writing practice, adopting terms of adventure and risk. She compares writing activity to diving into "seas of horror"(D1 20: 16 Jan. 1915) or to sending "parachutists into these remote places" of her mind (D5 289: 29 May 1940). I believe that Woolf`s illness and her attempt to explore the unknown part of her mind in her writing are closely related. Suffering from mental and physical illnesses, Woolf tried to sublimate the painful experiences into creativity. The relationship between her illness and creativity is a complex one. It seems that while her writing activity seems to have some therapeutic effects on her suffering, Woolf`s pursuit of a new mode of writing which she hoped to be more amenable to women by means of exploring the unknown may have aggravated her already precarious health. In this study, I ventured to look into Woolf`s daring expedition to these "undiscovered countries" in her mind and how such an exploration affected her literary experimentation and shaped her writing by reading "On Being Ill," and A Room of One`s Own, along with her autobiographical writings including her diary, with a particular reference to Julia Kristeva`s theoretical discussion of abjection.