Felicitas Villanueva says in a complaint filed in Manhattan federal court that Michael Hurley and Malu Custer Edwards violated human trafficking laws.
The 50-year-old says she began working for them in Chile in 2010.
She says she signed a contract to come to New York with the family in 2011 that she didn't understand.
She charges she was locked in rooms, forced to work many hours, physically beaten by children and denied medicine.
The lawsuit says both Hurley and Edwards come from wealthy aristocratic Chilean families.
Attorney Robin Alperstein says Villanueva's claims are without merit. She says they will be "fully refuted in court."