Gerald G. (Gerry) Wagner, 57, a leader in Washington film and international cultural circles, died of cancer yesterday at Georgetown University Hospital.

Born in Berlin of a department store family, Mr. Wagner came to America in 1936 with his uncle, the late Metropolitan Opera basso, Emmanuel List. He learned theater management in New England and then spent severals years in New York as stage manager of the Roxy Theater, then in its prime.

Mr. Wagner came to Washington as assistant to Louise Noonan Miller, a diplomat's wife who introduced foreign films to Washington at the Little Theater on 9th Street NW., which she had inherited. With Ilya Lopert as a New York-Paris associate, Mrs. Miller then developed the DuPont and Playhouse theaters, with her associate Mr. Wagner, taking over at her death.

Invitational and benefit premiers became a Wagner specialty, attracting such notables as Presidents Truman, Eisenhower, Kennedy and Johnson, the President of India, Lawrence (Lord) Olivier, Sir John Gielgud, Irving Berlin, Richard Burton and Rex Harrison. Mr. Wagner would put off a film opening until he had corralled what he considered "a worthy audience for a worthy cause."

He was decorated by the Italian and French governments for his promotion of Italian and French films in this country.

Such associations broadened Mr. Wagner's activities. He became Washington representative for Robert W. Dowling's far-flung City Investing Co., which controlled housing developments as well as the National Theater. Mr. Wagner also represented Dowling in his capacity as chairman of ANTA, the American National Theater and Academy.

During trips to Moscow for Dowling, Mr. Wagner, set up cultural exchanges between the United States and the Soviet Union, involving the Philadelphia Orchestra and the Bolshoi Ballet.

At the Playhouse he arranged the premiere of the first Soviet film exchange, "The Cranes are Flying," at the instigation of this policy in 1965.

For ANTA's Salute to France, he helped arrange the Helen Hayes-Mary Martin production of "The Skin of Our Teeth." At the request of Secretary of the Interior Stewart Udall, Mr. Wagner coordinated the TV broadcast and opening night of the reopening of Ford's Theater in 1968.

Forming his own international public relations firm, Mr. Wagner inaugurated the annual United Nations Concert and Dinner, which grew from a simple evening 17 years ago into major events at the Kennedy Center and Carnegie Hall.

As Washington representative for the Harkness Foundation, entailing overseas tours for the Harkness, Pearl Primus, Alvin Ailey and Robert Jofrey dance companies. Mr. Wagner noted the lack of suitable performing space in the White House East Room, where so many entertainments were given. He instituted action for improvements. Eventually president and Mrs. Johnson dedicated the chaste, white-columned stage, which had been designed by Jo Mielziner and donated by Rebekah Harkness.

A restless innovator, Mr. Wagner conceived the Bicentennial idea of taking U.N. ambassadors out of New York to the states. In 1976, they went to Nashville at the invitation of Tennessee Gov. Ray Blanton to visit the Grand Ole Opry's new homw.

Last June Mr. Wagner led the U.N. representatives to Pittsburgh, where Gov. Milton Sharp took them to a steel mill and a Pirates baseball game.

He is survived by his wife, Ruth, a former staff writer of The Washington; a son, Mark, a student at Massachusetts Institute of Technology; a daughter, Katherine, a student at Tufts University, and his mother, Anna Rosenthal Anopol, of Yonkers, N.Y.