Former Enron boss Jeffrey Skilling is asking a judge to overturn last month's court verdict that found him guilty of fraud and conspiracy at the firm.
Mr Skilling faces a substantial jail term
In a motion filed with the US District Court in Houston, Skilling claims that the evidence presented at the trial was "legally insufficient".
If the verdict will not be overturned, Skilling said he wants a retrial.
Along with Enron founder Kenneth Lay, Skilling was convicted of hiding Enron's debts before its 2001 collapse.
Sentencing is currently set for 23 October, and both face substantial jail terms.
Skilling was found guilty on 19 out of 28 counts, while Lay was found guilty on the six charges he faced.
Their 15-week trial in Houston followed four years of investigation by the Department of Justice's Enron Task Force.
A spokeswoman for the task force said it had no comment on Skilling's motion.
Skilling told reporters after the May trial that "some things work, some things don't".
"Obviously I am disappointed, but that's the way the system works."