Kenneth Lay, Enron's founder, and Jeffrey Skilling, the former chief executive, are accused of defrauding investors by concealing the corporate giant's unstable finances while selling millions in company stock.
Starting on Monday, each side has six hours to summarise the case that lasted more than 14 weeks and featured 54 government and defence witnesses, including Lay and Skilling.
The jury's deliberations are to begin on Wednesday.
The two men counter that no fraud occurred at Enron other than a few executives who skimmed millions from hidden scams.
They say a lethal combination of bad publicity and lost market confidence fuelled Enron's swift spiral into bankruptcy protection in December 2001.
Skilling, 52, faces 28 counts of fraud, conspiracy, insider trading and lying to auditors from 1999 to 2001.
Lay, 64, faces six counts of fraud and conspiracy focusing largely on his actions after he took over as CEO upon Skilling's departure.
Skilling (L) and Lay face more
than 30 years in jail if convicted
The case also represents the most high-profile test for the government's crackdown on corporate wrongdoing.
Ross Albert, a former prosecutor and Securities and Exchange Commission enforcement lawyer who practices in Atlanta, said that "in terms of resources, time spent on investigation, the number of attorneys involved, the Enron case has no counterpart in the annals of white-collar prosecutions".
A conviction would likely be a vindication for the government's Enron task force, set up in the aftermath of one of the worst scandals in recent history, which hurt confidence in corporate America.
In the trial itself, observers said the prosecution appeared to have presented a strong case, while the defence was marred by inconsistent testimony from Lay.
If convicted, both men could be sentenced to more than 30 years in jail.
Lay also faces a separate trial on federal banking violations, which will begin on May 18.