Walter Seligmann, 66, who retired in 1977 after 20 years as banquet manager of the Mayflower Hotel, died of a brain tumor Friday at the Chevy Chase Nursing and Convalescent Center in Silver Spring.

Mr. Seligmann joined the hotel as a busboy in 1937, and became banquet manager in 1957.

On his retirement, he received letters from President Carter and Mayor Washington and a number of awards, including the George Award from the Board of Trade and a distinguished service award from the Washington Area Convention and Visitors Association.

Mr. Seligmann was a native of Germany and came to Washington in 1936.

He was a member of the Ohr Kodesh Congregation in Chevy Chase Montgomery Lodge of B'nai B'rith. He also belonged to the Metropolitan Washington Board of Trade and the National Banquet Managers Guild.

Survivors include his wife, Else. of the home in Rockville; a son, Dr Ralph E., of Silver SPring; A daughter, Hele S. Horders, of New Orleans, and two grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the Scholarship Memorial Fund, c/o Pioneer Women in Silver Spring, or the Walter Seligmann Memorial Fund at George Washington University Hospital's neurosurgery department.