FBI spokesman James Margolin says 63-year-old Daniel Bonventre was arrested early Thursday at his Manhattan home.
The U.S. attorney's office says he is charged with conspiracy, securities fraud, and tax crimes. Bonventre was expected to appear in court later in the day.
Madoff is serving a 150-year prison sentence. He admitted cheating investors out of billions of dollars through an investment Ponzi scheme.
The name of Bonventre's attorney was not immediately known.
