"Crimes of this magnitude deserve severe punishment," Judge Sim Lake said when handing down the 292-month sentence.
Skilling, 52, who had faced a maximum of 185 years in jail, told the court he planned to appeal his conviction stemming from the 2001 collapse of the Houston-based energy giant under a mountain of shady deals.
"I am innocent of these charges," Skilling told the court.
Skilling also said that media reports which characterized him as unremorseful were wrong.
"Nothing could be further from the truth," he told the court.
"I can't imagine more remorse."
Skilling's co-defendant in the massive fraud case, Enron founder Kenneth Lay, died of heart failure in July.
Lay's conviction on 10 counts of fraud, conspiracy and banking violations was thrown out last week because he died before he could appeal the verdict.
Before Skilling's sentencing, the disgraced CEO faced a host of disgruntled former employees.
"You should be ashamed," said Ann Beliveaux, an 18-year employee who lost her entire retirement savings of 500,000 dollars.
"When things got bad, you jumped ship," she said, adding that Enron's collapse was "only because of your greed."
Kevin Hyatt, who worked for 17 years for Enron, said in the last five years of his employment he "witnessed a competitive, me-first culture."
This, he said, was a "virus actively cultivated by management."
Hyatt asked the judge to mitigate the wrongs and deception and to "send a message" to other corporate executives by giving Skilling the maximum
sentence.
Enron's spectacular collapse in 2001, then the largest corporate bankruptcy in history with more than 40 billion dollars in outstanding debt, rattled energy and stock markets.
Thousands lost their jobs and life savings.
While a raft of other business scandals followed, like Tyco, ImClone, Aldephia and Worldcom, it was Enron that became synonymous with corporate misconduct.
And Skilling and Lay personified greed for hiding company losses and hyping the stock's value while selling their own shares on the sly.
Legislators invoked their names to justify passage of the Sarbanes-Oxley Act, which aims to improve corporate governance by making executives and boards of public companies personally responsible for accounting statements.
Skilling and Lay were unrepentant throughout their widely publicized four-month trial.
They claimed they had done nothing wrong and asserted that Enron was a thriving company brought down by unfavorable news reports and the deceit of its chief financial officer, Andrew Fastow.
The government's charges were "a total misrepresentation of the facts," Skilling testified.
"I am devastated because a fine corporation was brought to its knees, in my view, unnecessarily."
Fastow, by contrast, was almost self-flagellating on the witness stand, proclaiming his shame and deep sorrow for helping his former bosses defraud the investing public through accounting and financial trickery.
Choking back tears, he testified: "I believe I was extremely greedy and that I lost my moral compass.
I've done terrible things that I very much regret."
Fastow pleaded guilty in 2004 and was the prosecution's most effective witness against Skilling and Lay.
He was sentenced to six years in prison last month. He had agreed to serve 10 years in jail but the judge cited his co-operation with prosecutors and his remorse as grounds for serving less time.