Dyonélio Tubino Machado (21 August 1895 - 19 June 1985) was a Brazilian writer, psychiatrist and political activist, one of the representatives of the second generation of Modernism in Brazil.

From 1924 to 1929, he studied Medicine in Porto Alegre, and specialized in psychiatry in Rio de Janeiro; in 1932 he published the thesis Uma definição biológica do crime advised by Antônio Austregésilo.

[2] With a growing interest in journalism and literature, he began to frequent the Porto Alegre circle known as "the Praça da Harmonia group," which included the doctor Celestino Prunes, Eduardo Guimarães, Alceu Wamosy, and Almir Alves.

[4][5] A dedicated member of the Brazilian Communist Party (PCB), Machado was elected, president of the regional section of the Aliança Nacional Libertadora (ANL) at a founding assembly at the São Pedro Theatre in Porto Alegre.

He became the leader of this group, in the Legislative Assembly of Rio Grande do Sul, which included Antonio Ribas Pinheiro Machado Neto and Otto Ohlweiler.