A 30-year-old woman from El Salvador has filed a suit in U.S. District Court here against an employee of the Organization of American States, alleging that she was forced to work 16 hours a day seven days a week as a house servant.

The suit, the second filed in little more than two weeks aginst an OAS employee alleging violations of a servant's rights, contends that the servant, Petrona Servillon, was forced to sleep on the living room couch and subjected to sexual harassment from the OAS employee's husband.

The suit asks for slightly more than $2 million in compensatory and punitive damages from Olga Petrovich Guye, a nonimmigrant employee of the OAS, and her husband, William R. Guye, a U.S. citizen, both of 11242 Cherry Hill Rd. in Beltsville. Mrs. Guye declined to comment on the suit yesterday.

According to the suit, Servillon came to the United States in May, 1975, after being recruited in her country by an agent for the Guyes. The suit claims she was promised $100 a month and a 5 1/2-day work week at eight hours a day, plus 15 days off after the first year.

Instead, the suit alleges, she was forced to work long hours and was the victim of assault and battery by Guye, that he physically abused her and attempted to force her to have sexual relations. In addition, the suit alleges that the Guyes kept $260 of her savings when she left their employment.

She eventually left the Guye's employ in October, 1976, 16 months after they hired her, when she learned through Washington radio station La Grande - which broadcasts in Spanish - where she could go for assistance.

Because she entered the United States under a special visa for nonimmigrants to work as a household employee of an international agency, her visa expited with her employment, her attorney, William R. Diaz-Fontana, Said yesterday. She is scheduled to leave the country May 12, he said.