The Hall of Fame golfer wrote in her blog that Ava Madelyn McGee was born Tuesday morning. She weighed 6 pounds, 10 ounces and was 19 inches long.
Sorenstam said both her and her daughter were doing well and that she was "very excited" about the new addition to the family.
Sorenstam retired from the LPGA Tour last year after 72 victories and 10 major titles, saying she wanted to start a business and a family.
She married Mike McGee in January near the couple's home in Orlando, Fla.