The advertisement, for H&R Block, was created by the Interpublic Group of Companies' agency Campbell Mithun. It will encourage people to avoid bad tax advice and end up overpaying their taxes.
Nelson famously got into trouble over payment of taxes during the 1980s and, as a consequence, was left with a large tax bill to pay off, courtesy of the IRS.
In the H&R Block ad, the bearded singer is being offered the chance to endorse shaving cream but his agent refuses, citing Nelson's legendary status.
The camera then cuts to the next meeting, where Nelson's accountant informs him he owes $30m in back taxes. H&R Block is keeping the remainder of the advertisement under wraps until the Super Bowl.
The 70-year-old singer has appeared in advertisements for brands such as Taco Bell and Gap in the past.
David Byers, senior vice-president and chief marketing officer for H&R Block, said: "Even though Willie Nelson is an icon, he isn't immune to bad tax advice, like many other Americans."
Super Bowl, the final game in the American football season, is one of the most expensive advertising slots in the world, and American brands often make ads specifically for the occasion, or at least use it to debut new campaigns.
Last year, it was a sign of the advertising recession that spots during the Super Bowl sold sluggishly and at lower rates than in previous years, where start-up dotcoms with huge marketing budgets pushed up prices for slots.
H&R Block's ad will show during the first quarter of the game, and it will back its advertising by sponsoring a pre-game show during which sports fans will be able to vote for their H&R "Block of the year".
Super Bowl XXXVII takes place on January 26 in San Diego.
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