"Joni remains under observation in the hospital and is resting comfortably. We are encouraged by her progress and she continues to improve and get stronger each day," the statement said.
The singer, 71, was taken to hospital on Tuesday. According to initial reports she was found unconscious at her home in Los Angeles, but a friend of the musician's later told CBC News the singer was conscious and that she had suffered a "minor medical emergency."
Mitchell is one of Canada's most accomplished musicians, famous for songs like Big Yellow Taxi and River.
She has won eight Grammy awards, including a lifetime achievement award in 2002. She was inducted into the Rock and Roll Hall of Fame in 1997.
The native of Fort Macleod, Alta., is also a member of the Canadian Music Hall of Fame and the Canadian Songwriters Hall of Fame.
She has a star on Canada's Walk of Fame in Toronto and a commemorative stamp, and is a companion of the Order of Canada.