Jorge Luis Borges: Along with Julio Cortazar, Borges is probably Argentina's best known writer.  His works are, as a rule, short.  He wrote no novels, concentrating on poetry, short stories, and essays.  He also undertook many projects of translation, and collaborated with his friend Adolfo Bioy Casares on works under the pseudonym H. Bustos Domecq.

Julio Cortazar:  Cortazar wrote various novels, the most famous of which, Rayuela (Hopscotch), is a superb example of experimental narrative style.  He also wrote many short stories, two of the more famous being Casa tomada and Axolotl.

Marco Denevi: Author of Rosaura a las diez, Ceremonia secreta, Araminta, o el poder,and Una familia argentina, among others. Denevi is known for his formal language and elevated style and many of his works are bitingly satirical of both Argentine society and the larger society of the modern world.

Juan Gelman:  Gelman is a poet, and some of his most moving poems deal with the dictatorship that ruled Argentina in the 70s and early 80s.  He lived for many years in exile, and currently resides in Mexico

Angélica Gorodischer: Gorodischer writes mostly Science Fiction, although some of my favorite stories of hers examine the place of women in Argentine society.

Alejandra Pizarnik: Pizarnik both wrote poetry and translated works from French into Spanish.  She lived for some time in Paris.  Although she was recognized for her poetry during her lifetime, she struggled with mental illness and died of a drug overdose, evidently intentional, in a psychiatric clinic.  One of her best-known works is La condesa sangrienta, a prose poem about the "bloody countess" Elizabeth Barthory

Syria Poletti:  Though not one of Argentina's most renowned authors, Poletti is one of my personal favorites.  Born in Italy, she made Argentina her home as a teenager; like so many Argentines, an immigrant. Her most famous work , Gente conmigo was evidently made into a movie, though I have been unable to find it. In the 60s and 70s she wrote both mysteries (the genre called "policial" in Spanish) and stories about Italian immigrants, and now she writes children's books.

Manuel Puig: Puig's novel The Kiss of the Spider Woman was made into both a movie and a Broadway play. Puig's style was often experimental, and he touched on many then-taboo themes such as homosexuality and human sexuality in general. He lived not only in Argentina but also in Brazil and Europe, and wrote in Portuguese as well as Spanish.

Ernesto Sábato:  Sábato, in Argentina, is usually considered Borges' equal and a philosophical rival.  Why he is nowhere near as well-known outside of Argentina as Borges is one of those little mysteries I at least don't claim to understand. His short novel El túnel was made into a movie, and along with Sobre héroes y tumbas, it is his best-known work.

Alfonsina Storni:  Storni is probably Argentina's best-known female poet. She is known for her biting criticisms of the social and gender norms of her time and her eloquent explorations of human sorrow,

Luisa Valenzuela:  Valenzuela, quite the opposite of Sábato, is better known outside Argentina than within, thought this may be changing. Cambio de armas is one of her better-known books.