Her press office said their plane crashed between Mendonça’s home town of Goiânia and Caratinga, a small city 220 miles north of Rio de Janeiro.
The rising star performed country music, in Brazil called sertanejo.
Minas Gerais state’s civil police also confirmed Mendonça’s death, without providing details about the cause of the accident, which occurred shortly before arrival.
Politicians, sports stars and fans all made tributes to the singer.
Mendonça was the most listened to artist in Brazil on Spotify last year, and set a record during the pandemic as she moved her concerts online.