After hearing about the girl's plight, the 'Umbrella' hitmaker took to twitter to show her support for 15-year-old Terri Bancroft, who was banned from her Welsh school after staging a Rihanna-style make-over, reported Daily Express online.
"U are my hero Terry Bancroft!!! The colour of your hair doesn't change who u are, you are an A-grade student (sic)," she posted on her twitter page.
Bancroft said she did not expect to get a message from the singing star.
"I was surprised. I am not sure how Rihanna found out about me. My friends have been making jokes about how I am her idol. It was weird because she is so famous and she knew that I existed. It was really nice for her to show her support and it meant the world to me. I am a big Rihanna fan and I love all her songs," Bancroft said.
She has now dyed her hair black and has been allowed to return to her school.