Lowell Berry Kilgore, 77, a retired research chemist for the Commerce Department, died of a heart attack Tuesday in Stuart, Fla., where he maintained a winter home. He lived in Bethesda.

Mr. Kilgore retired in 1970 as director of the chemical and rubber division in the Business and Defense Services Administration of the Commerce Department and as a trade consultant to the Office of the President. He had joined the industrial intelligence division of Commerce in 1946.

While with Commerce, Mr. Kilgore had been a member of the U.S. delegation to three conferences in Geneva, Switzerlan, of the General Agreement on Tariffs and Trade (GATT).

In World War II he had served with the U.S. Army in London, and then with an Army technical intelligence until in occupied Germany immediately after the war.

Mr. Kilgore was born in Lafferty, Ohio. A graduate of Oberlin College, he earned a doctorate in chemistry at Johns Hopkins University.

After working for the DuPont Rayon Co. and the Agriculture Department, he founded and directed the Kilgore Development Corp. here, which he later sold. He held 90 patents on chemicals and pharmaceuticals he had developed and was known for his work on insecticides, air deodorants and waterproof cellophane.

Mr. Kilgore was a founder of West-moreland Congregational Church here.

He is survived by his wife, Helen Ford Kilgore, of the home; a son, Daniel, of Gaithersburg; a daughter, Kathleen Houton, of Boston; a brother, William A., of Rockville, and two grandchildren.