Her withdrawal was announced by the United States Tennis Association.
Williams made her decision late Saturday before her season-ending match against her older sister, Venus, at the Sony Ericsson Championships at Doha, Qatar. Serena beat Venus 6-2, 7-6 (7-4).Sunday for the 35th title of her WTA career.
"I think I'm just going to be wiped out by the end of this," Serena said after beating the injured Caroline Wozniacki to advance to the final.
Williams' decision means Vania King, No. 78 in the latest women's world rankings, gets a chance to better her 4-5 career Fed Cup record.
Team USA captain Mary Joe Fernandez will use King, Melanie Oudin, Alexa Glatch and Liezel Huber in the Nov. 7-8 match-up against Roberta Vinci, Francesca Schiavone, Flavia Pennetta and Sara Errani.
Although Italy has never beaten the U.S. in Fed Cup competition, Vinci has lost just one of 15 career cup singles matches.