Her daughter Billie Lourd said the actress passed away on Tuesday morning after being taken ill travelling from London to Los Angeles.
She is survived by her mother, the veteran Hollywood star Debbie Reynolds who has been by her side along with her close family over Christmas.
Fans of Fisher had held out hope for her recovery following reports that she was "stable", with her uncle disclosing the family had believed there would be a positive outcome.
But a spokesman for the family said: “It is with a very deep sadness that Billie Lourd confirms that her beloved mother Carrie Fisher passed away at 8:55 this morning.
“She was loved by the world and she will be missed profoundly. Our entire family thanks you for your thoughts and prayers.”
Reynolds, 84, said: "Thank you to everyone who has embraced the gifts and talents of my beloved and amazing daughter.
"I am grateful for your thoughts and prayers that are now guiding her to her next stop. Love Carrie's Mother".
Fisher had been in hospital since December 23, when she fell ill on a United Airlines flight.