Dr. Mehmed A. Simsar, 78, a retired motion picture director with the old U.S. Information Agency and an authority on the Middle East, died of arteriosclerosis Saturday at George Washington University Hospital.

Dr. Simsar was born in Tabriz, Iran, and reared in Istanbul. After graduating from Robert College in Istanbul, he came to this country and earned master's and doctoral degrees in business at New York University.

During the early 1930s, he attended the University of Pennsylvania's oriental studies school and earned a master's and doctoral degrees there. During the mid-1930s and early 1940s, he taught Persian and Turkish literature at Princeton University.

Dr. Simsar began his government career in 1941 with the old Office of War Information in New York City, where he became chief of the Persian and Turkish desks. He then worked for the Voice of America in New York City for seven years before coming to Wahington in 1953.

He spent the next 12 years as a film producer-director with the USIA in Washington before retiring in 1965. He worked on films dealing with science and education. One of the films, "Beyound Silence," dealing with education of the deaf, was nominated for an Academy Award.

He was a research fellow of the Cleveland Museum of Art and the author of a number of works on the language, literature, art, and history of Iran.

Survivors include his wife of 43 years, Louise Dean Simsar of Washington.