It is the first administration role for the 53-year-old Republican fundraiser with telegenic looks who has long been an articulate surrogate for the president and who was first named to his transition team last November.
The son of a middle class Italian-American family from Long Island, Scaramucci cut his teeth in high finance at Goldman Sachs, the leading investment bank for which several senior Trump allies once worked.
Nicknamed "Mooch" on Wall Street, the always slick and dapper Scaramucci spent seven years at the bank before co-founding investment partnership Oscar Capital Management, which was sold in 2001.
In 2005, he founded global investment firm SkyBridge Capital, which for years ran a prominent annual conference in Las Vegas, which united the great and good of finance, international politics and the celebrity world.
Making no secret of his desire to join the Trump administration, the Harvard and Tufts-educated Scaramuccimoved to avoid any potential conflict of interest by announcing in January that he had sold his stake in SkyBridge.
He was last month named in a CNN article -- which was later retracted and led to the resignation of three journalists -- that claimed Congress was investigating links between Trump's administration and a Russian investment fund.
His tough response to the article reportedly won the admiration of his new boss.
In public he cultivates a polite and friendly persona, an agile figure on television as a former Friday night host of "Wall Street Weekly" on Fox Business, and as a former contributor at CNBC.
Reportedly respected by Trump's daughter Ivanka and son-in-law Jared Kushner, he was the sole emissary from Trump's transition team at the World Economic Forum in Davoslast January .
Having initially raised funds for the president's early Republican rivals Scott Walker and Jeb Bush in last year's election, he later joined Trump's national finance committee and his transition team in November 2016.
In 2012, he was national finance co-chair of the Republican nominee Mitt Romney's failed presidential run in 2012.
He is the author of three books: "The Little Book of Hedge Funds," "Goodbye Gordon Gekko" -- the greed-obsessed fictional tycoon played by Michael Douglas -- and "Hopping Over the Rabbit Hole: How Entrepreneurs Turn Failure into Success."
"If you decide to be an entrepreneur, the number one thing that you have to have in your personality is grit and perseverence," he said in a video posted to his official Facebook page to promote the book last year.
Skills that might come in useful for his new job.
