Kenneth Rice has become the latest former Enron executive to plead guilty to criminal charges in relation to the firm's collapse.
Kenneth Rice pleaded guilty in a federal court in Houston
Mr Rice admitted one count of securities fraud and agreed to co-operate with prosecutors in their case against other Enron executives.
Mr Rice ran Enron's broadband telecoms operation for two years, reporting to chief executive Jeffrey Skilling.
Mr Rice is to be sentenced in January and faces ten years maximum in jail.
Mr Rice admitted that, while chief executive of Enron Broadband Services, he had lied about the service's software capabilities and misled the financial community about its business fundamentals.
The deception helped boost the share price of parent company Enron, which collapsed in the midst of a massive accounting scandal in December 2001.
Mr Rice agreed to forfeit $13.7m and pay $1m to the Securities and Exchange Commission.
Separately, he has also agreed to pay $14.7m in civil fraud charges.
"The guilty plea is another sign that our efforts to clean up corruption in the boardroom have not stopped," said deputy attorney general James Comey.
Rice was the most senior of seven former executives at EBS charged with wrongdoing.
Former chief executive officer Andrew Fastow is the most senior former Enron executive to have pleaded guilty to criminal charges.
He was sentenced to ten years in jail.
Mr Skilling and former chairman Kenneth Lay have pleaded not guilty to more than three dozen counts of insider trading, fraud and lying on financial statements.