She will anchor a daily program for that network, plus a weekly business-oriented show for Fox News Channel.
She begins at the network Feb. 1, with both programs set to launch by April, the network announced Wednesday.
Her high-profile work and photogenic looks earned her the nickname "Money Honey."
Before arriving at CNBC in 1993, she spent five years as a producer, writer and assignment editor for CNN Business News.
She is the author of several books, including "The Weekend That Changed Wall Street" and "The 10 Laws of Enduring Success."
At her new workplace, she reunites with Roger Ailes, Fox News chairman and CEO, who previously ran CNBC.
Ailes said he is "delighted to have her join me once again."
Fox Business Network, which signed on in October 2007, is available in more than 70 million homes.