Earl Winfield Spencer, Jr. (September 20, 1888 - May 29, 1950) was a pioneering U.S. Navy pilot best known as the first husband of Wallis Simpson, who became the wife of the former Edward VIII of the United Kingdom and famed as Duchess of Windsor. He eventually rose to the rank of commander.

Known as Win, he was born in Kansas, a son of Earl Winfield Spencer, Sr and his wife, Agnes Lucy Hughes, and he attended Racine College in Racine, Wisconsin.

His first wife was Bessie Wallis Warfield (1896 - 1986), the only child of Teackle Wallis Warfield and his wife, Alice Montague. They were married in 1916 and divorced in 1927.

His second wife was Miriam J. Spencer. They were divorced in 1936.

His third wife was Norma Reese (1889 -), the widow of Homer Stuyvesant Johnson, a Detroit manufacturer. She was a daughter of Carl Reese. Spencer and Mrs. Johnson were married in Los Angeles, California, on July 4, 1937. The wedding was a double ceremony; the other couple was Norma Johnson's daughter, Betty Johnson, an actress and songwriter, and Balie Peyton Legare, Jr, a jazz musician known as Peyton Legare.

Norma and Earl Spencer separated on February 9, 1940 and were divorced later that year in Santa Monica, California. Both parties charged cruelty, and Norma Simpson declared that her husband was a plagued by what The New York Times's announcement of their acrimonious divorce delicately called "habitual intemperance."

Commander Spencer died in Coronado, California.