Joseph F. Castiello, 76, a retired labor relations lawyer who had a private practice in Washington from 1940 to 1984, died Aug. 16 at his home in Boca Raton, Fla. He had amyotrophic lateral sclerosis, also known as Lou Gehrig's disease.

Mr. Castiello graduated from Albright College in his native Pennsylvania and earned two law degrees at Catholic University. During the late 1930s, he was a trial attorney with the National Labor Relations Board.

In 1940, he joined what became the law firm of Hannon, Castiello and Berlow, where he specialized in labor relations law. During the 1940s and 1950s, he also taught labor relations law at Catholic University. He moved to Florida in 1977 but remained with the law firm until he retired last year.

Mr. Castiello was a past president of Counselors' Club of Washington and a member of the Kiwanis Club. He also was a past president of the Congressional Country Club and a member of St. Bartholomew's Catholic Church in Bethesda.

Survivors include his wife, Frances J., of Boca Raton; a son, Dr. Richard J., of Bethesda; three daughters, Margaret A. Mayer of Richmond, Joan L. Sweeney of Mountain Lakes, N.J., and Mary F. Peduzzi of Jeuno Isles, Fla.; a brother Pasquale, of Bethlehem, Pa.; six sisters, Louise Sorrentino, Rose Castiello, Lucy Conti and Antoinette Maioriello, all of Bethlehem, Anna M. Cianci of Reading, Pa., and Mary Schwechten of Roswell, N.M., and 11 grandchildren.