Nike, which has worked with the Russian for over 11 years now, has extended the contract by eight years, reports The Sydney Morning Herald.
A source with information on deal revealed that the deal, which takes effect in Jan 2010, includes a line of dresses designed by the 22-year-old Wimbledon champion.
Sharapova will also get a percentage of sales, the source added.
According to a report in Sports Illustrated, the former top ranked players earns an estimated 22 million dollars a year through prize money and endorsement.
The endorsement deals include those with big brands such as Tiffany & Co, Sony Ericsson and Canon.