Rabbi Isadore Breslau, 81, a Washington businessman who was active in Zionist and Jewish organizations, died of Parkinson's disease Saturday at Washington Hospital Center.

He was president of the Louis D. Bramdels Zionist district of the Zionist Organization of America in Washington from the mid-1930s to 1940, then served for three years as the organization's national vice president.

Rabbi Breslau also served as a national chairman of the United Jewish appeal during the 1960s, and was president and chairman of the United Jewish Appeal of Greater Washington during the 1950s.

He had been general chairman of the Washington committee for State of Israel Bonds, and was president of the American Association of Jewish Education from 1964 to 1972.

Born in Russia, he came to this country in 1906. He was a graduate of New York State College and Union Law School in Albany, N.Y. and was ordained after graduating from the Jewish Institute of Religion in New York City.

Rabbi Breslau led congregations in New York City and Waterbury, Conn. before moving here in 1933.

He entered the textile business in Washington and was president of the Mill End Shops.

A veteran of both world wars, he served in the Navy aboard a battleship in World War I, and as an Army chaplain in Europe during World War II.

He helped found the Jewish Community Council of Greater Washington, and was its president from 1949 to 1953.

His awards included a blonne plaque from the Jewish Community Council of Greater Washington, and a scroll in 1957 for his "leadership in the Jewish community of Washington and for services to the State of Israel" from the American Technion Society.

He was a member of Temple Sinai in Washington and BNai Israel Congregation in Rockville.

He is survived by his wife Julia D. of the home in Washington; a son, Joel of Chevy Chase; a daughter, Rith Fein, of Waban. Mass; four sisters, Flora Nachman and Sophie Breslaw, both of Albany, and Rose Rosenblast and Faith Cummins, both of New York City; two brothers, Dr. William Breslaw, of Florida and Morris Breslaw, of Albany and eight grandchildren.