Flávio José Arns (born 9 November 1950) is a federal senator of Brazil representing his home state of Paraná.

[2] Of German descent, he is grandson of Gabriel Arns and Helene Steiner.

in Linguistics with his thesis focusing on language and behavior from Northwestern University in the United States.

[5] Following him taking seat in the senate he was elected vice chair of the Commission on Education, Culture and Sport.

[8][9] A strong supporter of the rights of those with autism and other developmental disabilities, in September 2016 Arns was recognized by the senate of Paraná for his political activism.

[10] Arns has faced some controversy for allegedly hiring Rosângela Wolff, the wife of judge Sergio Moro, as a legal adviser in 2015.

Judges are prohibited to communicate with active politicians in Brazil, and Wolff denied that she ever formally worked for Arns.

[11] On 31 August 2020 Arns announced that he had left the Sustainability Network and joined the Podemos party in the Brazilian senate.