Louise Van Harlingen Ingersoll, 95, a soprano who had sung in concert, oratorio and opera, died of congestive heart failure Monday at her home in Washington.

She was the widow of retired Navy Adm. Royal Eason Ingersoll, commander in chief of the Atlantic Fleet during three years of World War II. After his retirement in 1945, they had maintained homes in Washington and LaPorte, Ind. Adm. Ingersoll died here in 1976.

Mrs. Ingersoll was born in Richmond, Ind. She studied voice at Oberlin College in Ohio, Agnes Scott College in Georgia and in New York.

Mrs. Ingersoll had traveled extensively with her husband, including tours of duty in the Far East. She christened the submarine, Gato, during the early part of World War II and was sponsor in 1979 of the Ingersoll, a Spruance-class multimission destroyer named in honor of her late husband.

She had been president of the Society of Sponsors of the U.S. Navy. She was an active member of the National Society of Colonial Dames, the Magna Carta Dames, the Huguenot Society and the Daughters of the American Revolution. She also had published a genealogical book on the Lanier family in America.

She is survived by a daughter, Alice Nagle, of Washington, and two grandchildren. A son, Navy Lt. Royal Rodney Ingersoll II, was killed in the Pacific in World War II.