The Beija Flor school showed the country with a huge rat in charge, while politicians were seen holding briefcases lined with gold.
Beija Flor beat 12 other schools to win the top prize at the carnival for a 14th time. Preparations for the parade begin months in advance.
Entrants in the competition often adopt a political theme.
The second-placed school also criticised Brazilian leaders in their entry, depicting President Michel Temer as a vampire.
Photos at The Sun.