The Vegetarian received mainly positive reviews from critics.
Boyd Tomkin, chairman of the 2016 Man Booker International Prize judging panel, lauded the book for its "disturbing outlook on a subject of vast interest", and Smith's "creative effort for blending beauty and horror". He commented, "This compact, exquisite, and disturbing book will linger long in the minds, and maybe the dreams, of its readers. Deborah Smith's perfectly judged translation matches its uncanny blend of beauty and horror at every turn."
Julia Pascal, writing for The Independent said, "It is the women who are killed for daring to establish their own identity. The narrative makes it clear it is the crushing pressure of Korean etiquette which murders them. Han Kang is well served by Deborah Smith's subtle translation in this disturbing book." Porochista Khakpour, writing for The New York Times, states that the book is nothing like typical stories about vegetarianism that end with "enlightenment". She compares the work with African-Australian author Ceridwen Dovey's novella Blood Kin, American author Herman Melville's 1853 short story "Bartleby, the Scrivener", Iranian author Sadegh Hedayat's 1937 cult horror story The Blind Owl, and various journals and works of Czech author Franz Kafka, including A Hunger Artist.
Calling it "an extraordinary story of family fallout", Daniel Hahn of The Guardian wrote, "Sentence by sentence, The Vegetarian is an extraordinary experience. Last year’s London Book Fair had Korea as guest of honour, in the hope of tempting English-language publishers to seek out more contemporary Korean novelists, but The Vegetarian will be hard to beat. It is sensual, provocative and violent, ripe with potent images, startling colors and disturbing questions." Claire Fallon, writing for The Huffington Post, called it "an elegant tale, in three parts, of a woman whose sudden turn to veganism disrupts her family and exposes the worst human appetites and impulses". Calling it a melancholic tale of something more than vegetarianism, Thrity Umrigar, writing in The Boston Globe, described The Vegetarian as a tale of a woman torn between a stock of her own cautious and conventional life choices and her family members who are not as innocent as they seem to be.
Gabe Habash of Publishers Weekly called it an ingenious, upsetting, and unforgettable novel. He added, "There is much to admire in Han's novel. Its three-part structure is brilliant, gradually digging deeper and deeper into darker and darker places; the writing is spare and haunting; but perhaps most memorable is its crushing climax, a phantasmagoric yet emotionally true moment that's surely one of the year's most powerful". He compared its parts to Patrick Süskind's Perfume, Herman Koch's The Dinner, and Hanya Yanagihara's A Little Life respectively. Eileen Battersby, writing for The Irish Times, said, "The Vegetarian is more than a cautionary tale about the brutal treatment of women: it is a meditation on suffering and grief. It is about escape and how a dreamer takes flight. Most of all, it is about the emptiness and rage of discovering there is nothing to be done when all hope and comfort fails. For all the graphic, often choreographed description, Han Kang has mastered eloquent restraint in a work of savage beauty and unnerving physicality." Laura Miller, writing for Slate, compares the straightforward style of writing with works by the Japanese author Haruki Murakami.