TMZ has reported the singer was in her Pasadena home in California with her husband Dion, when she started to complain that she couldn't breathe.
The US publication alleges Dion called the ambulance before performing emergency CPR on his wife until paramedics arrived on the scene. Freeman was pronounced dead at the local hospital at around 5:30pm.
Since the news broke, The Voice judge Miley Cyrus took to her Instagram story to show her condolences.
"Thank you @janicefreeman.. for everything," wrote Cyrus on a photo of a rainbow. "This represents you perfectly."
Freeman — who competed on Cyrus' team during season 13 of the reality singing show, has previously battled lupus, cervical cancer and meningitis.
Our thoughts and prayers are with Freedman's family.