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. My son and I would like to thank the doctors, nurses, and staff of Mount Sinai Hospital for the amazing care they provided for my mother.
"Cooper and I have found ourselves humbled by the outpouring of love, support, and prayers we have received from around the world. They have been heard and appreciated.
"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."
Joan had been on life support for almost a week at Mount Sinai hospital after she stopped breathing and suffered a cardiac arrest during surgery on her vocal chords at a nearby private clinic.
She had been moved out of intensive care and taken off life support on Thursday morning, where she was "kept comfortable" in a private room in hospital.
An actress, writer, producer, and TV host of the incredibly successful Fashion Police, Joan's career began in the late 1950s.
She starred in several plays in New York, and by the 1960s, she had featured with Johnny Carson on The Tonight Show.
Over the following decades she began to make a name for herself on various variety and comedy shows, and by the 1980s had become a regular on The Tonight Show, where she honed her particular style of comedy, which involved poking fun at celebrities and also herself.
A pioneer, Joan's confrontational, confessional, and often aggressive comedic style riled many but provided a pathway for other female stand-ups to emerge and go toe-to-toe with male comics.
In the 1980s, Joan hosted a rival show to The Tonight Show, which put an end to her friendship with Johnny Carson, and in 1989 she won her first, and only, Emmy for The Joan Rivers Show.
Joan was married twice, and never remarried after her second husband, Edgar Rosenberg died.
She leaves behind one daughter, Melissa.