John Snow, a retired security officer with the British Embassy in Washington, died of a heart ailment Aug. 23 in a hospital in Moncton, New Brunswick, Canada.

Mr. Snow came to Washington in 1950 and worked at the British Embassy until the early 1960s. He then remained in Washington and was a credit manager for Hollywood Clothing and Kay Jewelers before retiring about 1973.

He was a native of Halifax, Nova Scotia, and since leaving Washington two years ago, has lived in Riverview, New Brunswick. Mr. Snow served in the Royal Canadian Army during World War I, and was an officer in the Royal Canadian Mounted Police for 20 years before retiring in 1947.

Mr. Snow's first wife, the former Auldis E. McDonald, died in the early 1930s.

Survivors include his second wife of 45 years, the former Margie Woodworth, of Riverview; two sons, Donald, of Edmonton, Alberta, and Weldon, of Riverview, and a daughter, Beatrice Snow of Victoria, British Columbia, all by his first marriage; three daughters by his second marriage, Jacqueline Singmaster of Edgewater, Md., Jean Burch of Suitland, and Joan Bledsoe of Landover; a brother, William, of Fall River, Nova Scotia; 25 grandchildren, and seven great-grandchildren.