Spilman replaces Elisa Steele, who was behind Yahoo’s $100m 'It's You' campaign, and left the company at the end of last year, shortly after former chief executive Carol Bartz was dismissed.
Spilman was head of Americas marketing at Yahoo for two years and before that, was a consultant for business-to-business marketing at the company.
Prior to Yahoo, Spilman worked as chief sales and marketing officer at AOL's Advertsing.com.
As part of the management reshuffle, Yahoo has named Mickie Rosen, senior vice-president of Yahoo Media Network, as head of global media and commerce.
The company has also confirmed that Sam Shrauger, a former executive at Ebay's PayPal, who was hired last month as senior vice-president for commerce, is leaving the company.
It is understood that Robert Bridge, Yahoo's top marketer across EMEA, is unaffected by Spilman's appointment.
The reshuffle at Yahoo follows just a week after the controversial departure of chief executive Scott Thompson.
Yahoo has also announced that it has reached a deal to sell half of its 40% stake in Chinese internet giant Alibaba.
The deal would see Yahoo raise about $7.1bn (£4.5bn), composed of at least $6.3bn (£3.9bn) in cash proceeds and up to $800m (£506m) in newly issued Alibaba preferred stock.
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