The notoriously sharp-tongued comic had stopped breathing and gone into cardiac arrest at Mount Sinai Hospital in Manhattan last week while undergoing an operation on her vocal chords.
She was put on a life support system until the day before her death when she was moved out of intensive care and “kept comfortable”, but her condition deteriorated.
In a statement, her daughter Melissa Rivers said: “It is with great sadness that I announce the death of my mother, Joan Rivers.
“She passed peacefully at 1.17pm, surrounded by family and close friends.”
She added: “My mother’s greatest joy in life was to make people laugh.
“Although that is difficult to do right now, I know her final wish would be that we return to laughing soon.”