When The Unbearable Lightness of Being appeared in 1984, it immediately became an international bestseller, garnering awards throughout the world, including a Los Angeles Times Book Award. Contemporary reviews of the novel were largely positive. Paul Gray, in a Time review, calls The Unbearable Lightness of Being "a triumph of wisdom over bitterness, hope over despair." Maureen Howard in the Yale Review writes, "The Unbearable Lightness of Being is the most rewarding new novel I've read in years." Thomas DePietro in Commonweal hones in on the heart of the book. He observes that The Unbearable Lightness of Being is a book of "burning compassion, extraordinary intelligence, and dazzling artistry." DePietro also notes the book "leaves us with many questions, questions about love and death, about love and transcendence. These are our burdens, the existential questions that never change but need to be asked anew."

Not all reviewers were enchanted with the book, however. Christopher Hawtree, in a Spectator review, faults Kundera for a "most off-putting" title and finds irksome the "elliptical structure" of the work. With faint praise, however, he acknowledges the novel is "a self-referential whole that manages not to alienate the reader." Wendy Lesser in the Hudson Review is even blunter, calling The Unbearable Lightness of Being "a bad novel." She particularly finds fault with Kundera's characterizations:

The mistake Kundera makes is to treat his characters like pets. He thinks what he feels for them is love, whereas it's merely an excess of self. If it were really love, we would be able to push aside that gigantic authorial face that looms out of the pages of Kundera's novel . . . and find behind it the tiny, human, flawed faces of real novelistic characters. But they aren't there. Behind that leering, all-obliterating mask is nothing.

Scholarly interest in The Unbearable Lightness of Being continues unabated. Literary critics have found a variety of ways to read the novel. For example, John O'Brien in his book Milan Kundera and Feminism focuses on Kundera's representation of woman. He most notably studies the relationship between Tereza and Sabina, suggesting that Tereza represents "weight" and Sabina represents "lightness." O'Brien next demonstrates how Kundera undermines such an easy dichotomy. Finally, he argues that it is in Sabina's painting that Kundera reveals his true focal point.

In Terminal Paradox, scholar Maria Nemcová Banerjee takes another tact, reading the novel as if it were a piece of music. Just as Tereza introduces Tomas to Beethoven's quartets, and thus to the seminal phrase Es muss sein, Kundera introduces the reader to a quartet of characters: "The four leading characters perform their parts in concert, like instruments in a musical quartet, each playing his or her existential code in strict relation to those of the others, often spatially separated but never imaginatively isolated in the reader's mind."

Finally, Kamila Kinyon in Critique uses the French critical theory of Michel Foucault and the notion of the "panopticon" to analyze the book. Panopticon literally means "all-seeing," and it suggests a kind of surveillance mechanism. As Kinyon argues, "Within Kundera's novel, in a system of totalitarian Marxism where 'God is dead,' [the terrifying mystery] of God's gaze is replaced by [the terrifying mystery] of the panopticon camera, which may be directed at the individual at any time and which thus controls behavior even at those times when it is physically absent."