Sharapova, who won Wimbledon last year at the age of 17, is already appearing in advertising for Palmolive deodorant, which is running across Europe. In the US, she will represent the Lady Speed Stick brand.
Colgate-Palmolive said the 18-year-old's beauty, grace and active lifestyle made her a perfect ambassador for Palmolive's brand values of protection, reliability and confidence.
Sharapova said: "These products are such a part of both my personal and professional life -- there's such a natural connection for me. I'm looking forward to working with them for years to come."
Sharapova, who is now the number two ranked tennis player in the world, also has deals with TAG Heuer, Motorola and a deal with the company Parlux Fragrances to make her own fragrance.
She also appears in the latest Nike campaign, along with stars such as fellow Wimbledon champion Roger Federer and the marathon runner Paula Radcliffe.
The deal with Colgate-Palmolive was negotiated by IMG, Sharapova's management company.
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