After Thiago de Mello completed his elementary education at the Grupo Escolar Barão do Rio Branco and high school at the Gymnásio Pedro II in Manaus, he moved to Rio de Janeiro, where he enrolled in the Faculty of Medicine (Faculdade Nacional de Medicina), but left after four years to pursue the path of poetry.

[2] In 1964, he wrote what is probably his best-known poem, Os Estatutos do Homem ( "The Statutes of Man"), which proclaimed simple human rights as a protest against the military regime and was allegedly immediately banned by it.

After the end of the Brazilian military dictatorship, he moved back to his native city of Barreirinha, where he lived in a house owned by the architect Lúcio Costa and worked for the integrity of the Amazon region and for human rights.

Besides his own work, he had a long career as a translator of Latin American poetry by Pablo Neruda, César Vallejo, Ernesto Cardenal, Eliseo Diego, Nicolás Guillén, and also T. S. Eliot into Portuguese.

His own works have appeared in Chile, Cuba, Argentina, Portugal, the United States, France, Great Britain and Germany, in addition to Brazil.