George Locke Howe, 79, a retired well-known architect in Washington who became even better known as an author, died Sunday at the Veterans Administration Hospital in Salem, Va., following surgery.

He had practiced architecture here with a series of partners from 1940 until about 1963. His firms designed and built more than 600 structures, most of them residential and many of them in Georgetown. They also designed some commercial and diplomatic buildings.

Mr. Howe was the author of a number of books but first gained attention as an author for his novel, "Call It Treason," which won first prize in 1949 in a book and play contest sponsored by the Christophers, an organization devoted to bringing Christian principles into everyday life.

The book was based on his experiences in World War II when he served as a civilian with the Office of Strategic Services and was attached to the 7th Army in Algiers and France, working on operations of agents behind enemy lines.

Mr. Howe produced the novel while he was a patient at the old Emergency Hospital here after he was severely injured in an automobile accident. He dictated it and it was transcribed for him.

"Call It Treason" was published in six foreign languages and later was filmed by 20th Century Fox under the title, "Decision before Dawn."

Mr. Howe also was the author of "Mt. Hope," a historical book about his native Bristol, R.I. He wrote several other novels and short stories that were published in Harpers magazine and poems that appeared in the New Yorker.

He graduated magna cum laude in 1918 from Harvard College, where he was elected to Phi Beta Kappa. After serving in Ireland with the Navy in World War I, he went on two archeological missions to Carthage and to the pyramids at El Matanieh, Egypt.

Mr. Howe returned to Harvard, where he received a master's degree in architecture in 1925. He then practiced with his father, the late Wallis Howe, also an architect, in Providence, R.I.

He came to Washington in 1934 to serve with the Public Buildings Administration before returning to private practice.

For many years, Mr. Howe and his family lived on a large farm near Fulton in Howard County, Md., where they raised beef cattle and thorough-bred horses.

After his retirement in the 1960s, they moved to Slate Mills, Va., where they restored historic "La Grange." From 1968 until he was hospitalized recently, they owned "Lion's Share," an estate in Haywood, Va.

He is survived by his wife, Elisabeth Parker Howe; four children, Linda Howe Hale, of Reno, Nev.; Mrs. Henry Colt Jr., of Dedham, Mass.; Navy Radioman 1st Class George Locke Howe Jr., stationed in Hawaii, and Mrs. Lloyd Lee McPherson, of Blacksburg, Va.; two brothers, two sisters, and 11 grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to Harvard College or to St. George's School in Newport, R.I.