Eros the Bittersweet: An Essay (1986) is the first book of criticism by the Canadian poet, essayist, translator, and classicist Anne Carson.

A reworking of her 1981 doctoral thesis Odi et Amo Ergo Sum ("I Hate and I Love, Therefore I Am"),[1] Eros the Bittersweet "laid the groundwork for her subsequent publications, […] formulating the ideas on desire that would come to dominate her poetic output",[2] and establishing her "style of patterning her writings after classical Greek literature".

It examines eros as a simultaneous experience of pleasure and pain, as exemplified by a word of Sappho's creation: "glukupikron" (the "bittersweet" of the book's title).

[4] Carson considers how triangulations of desire appear in the writings of Sappho, ancient Greek novelists (Longus, Heliodorus, Achilles Tatius, and Chariton), and Plato (in his Phaedrus).

"[8] By the turn of the millennium, Eros the Bittersweet had also entered into the popular consciousness, voted onto the 1999 Modern Library Reader's List for the 100 Best Nonfiction books of the 20th century,[9] and mentioned (along with Autobiography of Red) in a 2004 episode of the television series The L Word.