Otto Maria Carpeaux (March 9, 1900 - February 3, 1978), born Otto Karpfen, was an Austro-Brazilian literary critic.

Carpeaux was born in 1900 in Vienna, Austria, in a Jewish family, and stayed there until 1939. In the University of Vienna he studied exact sciences and received his PhD in Chemistry with a work concerning the brain, and possibly also a degree in Physics. Later he studied Sociology and Philosophy in Paris, Comparative literature in Naples, Politics in Berlin and, supposedly, Mathematics in Leipzig.

At some point in his life, Karpfen converted to Christianity, adding the Maria to his name and using Fidelis as his surname for some time. This conversion was evident in his political books (such as Wege Nach Rom) and his thinking, and led to his participation in the right-wing government of Engelbert Dollfuss.

When the Anschluss occurred and the Nazis took over Vienna, Karpfen went to Belgium. He stayed there for about a year and then came to Brazil, where he changed his last name to Carpeaux. At first he was given was a simple rural job, but eventually, through newspapers, he became an established literary critic, introducing writers such as Kafka and Musil to Brazilian audiences, along with the literary criticism of Dilthey, Croce, Benjamin and others.

Perhaps the peak of Carpeaux's production was his eight-volume History of Western Literature, unfortunately available only in Portuguese. Late critic José Lino Grünewald labelled it one of the brightest moments of the language in prose, despite the fact that Carpeaux was not a native speaker. It was written over a period of two years with a limited amount of research; the author depended primarily on his memory. It is also unique in that it focuses on creating links between all periods, in order to create an organic vision of the literary history he is telling. The book also include more than 8,000 brief criticisms and expositions of the majority of the figures discussed along the way.

After a transition to the Brazilian left, marked by his fight against the military dictatorship which came to power in 1964, Carpeaux abandoned his literary writings by 1968, although he participated in an encyclopedia called Mirador. He died of a heart attack in 1978.

Recently, his essays have been compiled by Brazilian philosopher Olavo de Carvalho, with an added introduction. Critic Mauro Souza Ventura released De Karpfen a Carpeaux, a study in the life and work of Carpeaux. Carpeaux's other works include a dense history of German Literature, several books of literary criticism, a popular History of Western Music and various political writings.