Oxley's wife, Patricia, says her husband died in his sleep early Friday in northern Virginia.
Oxley spent 25 years in Congress, where he devoted most of his time to issues involving corporate oversight and insurance protection.
The Republican who retired from the House in 2007 led an effort to investigate failed energy giant Enron and helped create new accounting requirements in the 2002 Sarbanes-Oxley Act.
The law reshaped corporate oversight after accounting scandals at Enron, WorldCom and other major corporations wiped out retirement accounts and cost investors billions.
Oxley was from Findlay. He rarely faced a close election in his rural northwest Ohio district.