Two representives of minority employe organizations filed a $3 million suit in U.S. court yesterday against Librarian of Congress Daniel J. Boorstin, charging him and the library's administration with "retaliatory, discriminatory and unlawful empolyment practices" and violation of their constitutional rights.

George E. Perry and Howard R. L. Cook alleged that they were subjected to harsh disciplinary measures-Perry was dismissed from the library's staff in 1977 and Cook was suspended without pay for 90 days-because they had testified in Congress against Boorstin's appointment as librarian.

They also contended in court papers filed yesterday that they were subject to harassment by the library's administration as they tried to organize its minority and black employes.

Perry is president of the Ethnic Employes of the Library of Congress, which claims a membership of about 250 people.Cook is executive director of the Black Employes of the Library of Congress, which claims about 800 members. The total staff of the library is close to 5,000.

John J. Kominski, the library's general counsel, said yesterday that the disciplinary actions were taken against the two employes because allegations they made against Perry's former supervisor in the Slavic Division were "false and maliciou." Boorstin, he said, "did not intervene in these actions holding any kind of grudge" or in any way to "affect those decisions by the director of personnel."