Sidonie Fiadanantsoa (born 30 April 1999) is a track and field athlete from Madagascar.

[2] She ran a 60m hurdles personal best at the 2022 World Athletics Indoor Championships, in Belgrade.

[3] She competed in the 100m hurdles at the 2022 World Athletics Championships, in Eugene, Oregon.

[4] She was a gold medalist in the 100m hurdles at the 2023 Francophone Games in Kinshasa in a time of 13.01 seconds.

[3] In March 2024, she was the flag bearer for her country at the 2023 Africa Games in Accra, Ghana.