According to court documents obtained by TMZ, Mayer may have been paid with money stolen from investors in a scam masterminded by conman Darren Berg.
Berg has been sentenced to 18 years in prison for apparently embezzling millions of dollars through a fake investment company.
Trustees are now in the process of trying to recover up to $465,000 (£290,354), which may have been paid to Mayer and his booking agency by Berg's company.
Mayer's attorney said of the lawsuit: "John Mayer performed at a corporate event in 2008 and was paid for his services.
"The opportunity was brought to John through his talent agency CAA."
Mayer is currently in recovery after vocal cord surgery.