The US$11b (A$14b) fraud forced the telecom giant into bankruptcy in 2002.
The result is seen as a triumph for both the US Justice Department and Wall Street, with the 63-year-old Ebbers found guilty of securities fraud, conspiracy and filing false reports with regulators.
Ebbers, who worked as a bouncer, basketball coach and milkman before getting into the telecommunications business faces a prison sentence of up to 85 years.
“Today’s verdict is a triumph of our legal system and the application of our nation’s laws against those who breach them,” said US Attorney General Alberto Gonzales.
“We are satisfied the jury saw what we did in this case: that fraud at WorldCom extended from the middle-management levels of this company, all the way to its top executive.”
Reid Weingarten, Ebbers’ lead defence attorney, said he was confident his client would be vindicated on appeal.
“CEOs have a responsibility but it doesn’t mean they’ve committed crimes when misdeeds were committed in their organisations that they didn’t know about,” the lawyer said.
“The captain of the ship is responsible for the ship, but is not criminally responsible unless he acted with criminal intent. And I don’t think Mr Ebbers ever acted with criminal intent and still don’t today, despite the verdict.”
Ebbers entered US corporate folklore, building a small Mississippi-based long distance company into a telecommunications powerhouse.
He cemented his reputation in 1998 with the $40b purchase of MCI Communications, the largest acquisition in corporate history at the time.
Cost-conscious and a stickler for odd details, he had been known to count the cars in company parking lots to see how many employees were working late and who was going home.
But he could also be a charming and folksy CEO, who preferred cowboy boots to suits, opened shareholder meetings with a prayer, ate lunch in the cafeteria and ran a company that had become a Wall Street darling by the late 1990s.
But the bursting of the ‘dotcom bubble’ saw WorldCom’s finances and popularity dive.
By late 2000, WorldCom accountants were making false entries to hide the financial problems from investors and the public before the company went bankrupt.
Ebbers maintained he was unaware of the fraud, and told the jury he would have put a stop to it had he known it was occurring
But the jury rejected his defence, sarcastically summed up by prosecutors as “Aw Shucks”.
The collapse of WorldCom, along with Enron, became a symbol of corporate misconduct, and inspired the US Congress to pass tough laws holding corporate leaders accountable for financial misconduct at their companies.
Top executives at Enron are due to go on trial next year in Texas.