Leigh Steinberg's attorneys filed the Chapter 7 petition in Orange County on Wednesday.
Steinberg said he takes full responsibility for millions of dollars of debt, telling The Associated Press that he "lost track" of his finances while he was in rehab. He said he struggled with alcohol for years but has been sober since 2010.
The bankruptcy filing comes weeks after a bench warrant was authorized for Steinberg after he failed to show up to a hearing for a $1.4 million debt case.
Steinberg has represented many NFL stars, including Troy Aikman, Steve Young and Ben Roethlisberger
The Associated Press contributed to this report.