She represented Brazil at the 2017 Artistic Gymnastics World Championships in Montreal, Quebec, Canada, where she placed fourth on the floor exercise.

[7] In September, Thais Fidelis represented Brazil at the 2016 Pan American Individual Event Artistic Gymnastics Championships.

In March, Thais represented Brazil at the City of Jesolo Trophy where she earned a silver medal with the Brazilian team, behind the United States and ahead of Russia.

In September, Thais competed at the Varna Challenge Cup where she earned gold on the floor exercise and bronze on the uneven bars.

In September, Filedis competed at the Pan American Championships where she earned the silver medal with the Brazilian team.