The book is about a Mexican bookseller who is forced to flee as an undocumented immigrant to the United States, along with her son, after her journalist husband exposes a local drug kingpin.

Lydia Quixano Pérez lives a comfortable life in Acapulco, Mexico, with her journalist husband, Sebastián, and her eight-year-old son, Luca.

Lydia runs a bookstore and one day befriends a charming customer, Javier, who appears to have similar interests in books.

Flatiron engaged in a massive publicity campaign, including sending boxes of copies to libraries near the Mexican border, holding a release party, and obtaining blurbs from Stephen King, Sandra Cisneros, Don Winslow and John Grisham.

[10] Oprah Winfrey, in selecting American Dirt for her book club, said, "Jeanine Cummins accomplished a remarkable feat, literally putting us in the shoes of migrants and making us feel their anguish and desperation to live in freedom.

"[11] The book also received glowing reviews from Mexican-American writer Sandra Cisneros, who called it "the great novel of las Americas" and "the international story of our time"[12] and Washington Post critic Polly Rosenwaike, who wrote that it "offers both a vital chronicle of contemporary Latin American migrant experience and a profoundly moving reading experience."

"[16] On Medium, writer David Bowles called the book "harmful, appropriating, inaccurate, trauma-porn melodrama.

"[17] In a January 30, 2020 opinion piece in The Guardian, author and critic Daniel Olivas wrote: "American Dirt is an insult to Latinx writers who have toiled – some of us for decades – to little notice of major publishers and book reviewers, while building a vast collection of breathtaking, authentic literature often published by university and independent presses on shoestring budgets.

"[18] A group of Latino writers formed a campaign and hashtag in response to the publication and initial mainstream praise of American Dirt called "#DignidadLiteraria" ("Literary Dignity").

On February 3, 2020, the group met with Macmillan, the owner of Flatiron Books, to demand greater representation of Latino writers under the publication house.

"[20] VanDenburgh also criticized Cummins' choice to position the main character as "forced" to illegally cross the border "by an all-powerful villain" which, she argues, makes it easier for sheltered, white American readers to sympathize with the plot.

[24] Asked about American Dirt in 2023, Mexican screenwriter Guillermo Arriaga praised it, and said that neither he nor anyone he discussed it with in Mexico felt that the author was out of bounds.

[25] On February 10, 2020, Dignidad Literaria confirmed from Flatiron Books that Jeanine had not specifically received death threats.

[26] That same day, 82 writers signed an open letter to Oprah Winfrey, calling the book "exploitative, oversimplified, and ill-informed", and asking her to rescind her endorsement.