Don’t mess with Lady Gaga.

The wild-styled singer fired back at her former producer Friday in a lawsuit saying he’s the one who broke the law by duping her into signing an illegal contract.

Lady Gaga’s ex-lover and producer, Rob Fusari, sued the singer for more than $30 million on Thursday, claiming he came up with her stage name and co-wrote some of her hit songs.

But Gaga’s lawsuit says the contract between her and Fusari is invalid because Fusari was not a licensed talent agent.

Not only do Gaga’s lawyers want Fusari’s suit thrown out, they want him to pay damages to the superstar singer for trying to take advantage of an “inexperienced performing artist.”

Fusari made Lady Gaga, whose real name is Stefani Germanotta, “enter into an unlawful arrangement” when he made her sign a contract giving him rights to her future earnings, the suit says, calling his actions “predatory and financially abusive.”

“The … arrangement was structured in such a way as to mask its true purpose – to provide the defendant unlawful compensation for their services as unlicensed employment agents,” the suit says.

Germanotta and Fusari met in March 2006 when he was looking for a female rocker with “garage band chops,” according to his lawsuit.

The producer, who worked with Destiny’s Child on “Bootylicious,” says he persuaded Germanotta to add dance beats to her music and call herself Lady Gaga.

Fusari’s lawyer, Robert Meloni, called the claim “ludicrous” when he read the suit last night.

“Rob was no more of an ‘agent’ for her than she is a Roman Catholic nun,” Meloni said.