A serial “sexual predator” posed as a restaurant owner and called one of his underlings for sexual favors, a new lawsuit alleges.

Steven F. Ferris allegedly phoned a hostess working at Soho greasy spoon Charlie Bird pretending to be her boss Robert Bohr and offered her $1,200 to meet Bohr’s “nerdy, older friend and client” and take off her clothes “while the ‘friend’ pleasured himself,” according to the new Manhattan Supreme Court Lawsuit.

“As a result of her discussions with Ferris, the host believed that Bohr had solicited her to engage in sexual acts with one of Bohr’s friends,” the court documents say.

The unidentified hostess “was so convinced of [Ferris’] lies that she hired a lawyer to explore bringing civil claims against Bohr” and the restaurant’s parent company, the suit says, adding the hostess was “traumatized” and Bohr was “humiliated” by the ordeal, the suit says.

The restaurant was forced to pay $90,000 in lawyer and private investigator fees to make sure there was no truth to her allegations, the court documents say.

In the end, the investigators tracked the call back to a number that Ferris allegedly used when he similarly harassed others by phone throughout the years, the court papers claim.

Ferris, 62, has a 38-year-history of prior arrests and six convictions for sexually harassing victims over the phone, and has prior arrests priors in Nassau, Suffolk, Queens and Manhattan dating back as early as 1990, court papers allege.

The Suffolk County District Attorney’s office said Ferris copped a plea in an incident involving a 16-year-old for one count of attempted endangering the welfare of child in 1998 — and was sentenced to a year probation and a $500 fine.

The Queens DA’s office confirmed Ferris pleaded guilty to a violation in 1992 but further details on the case were not immediately available.

Some of the cases, which the lawsuit says were sealed, could not immediately be confirmed.

The restaurant and Bohr are suing Ferris for $140,000.

Ferris did not answer the number he allegedly called the victims from. A woman reached at a different number listed for Ferris hung up the phone upon request for comment from him.

It was not immediately known if Ferris had a lawyer.