Russia, champions in 2004 and 2005, play Spain in Moscow in April next year and the world number three said she expected to be involved.
"I'm really excited to make my first appearance in the Fed Cup for my country and it is great to be playing the tie in Moscow," she said.
"Hopefully, myself and the team will put up a strong showing against Spain, who have a good team."
Sharapova was born in Nyagan, Siberia, but moved to Florida as a nine-year-old to train at Nick Bollettieri's famed Academy.
Sharapova always claimed she intended to play for Russia, although doubts were raised earlier this year when she opted out of the country's tie against Belgium in March.
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