Minnie de Foix Long Wilson, 79, a retired examiner for the General Accounting Office and a Washington-area resident since the early 1940s, died of cancer Monday at her home in McLean.

Mrs. Wilson joined the GAO in 1943 as an analyst.She was an examiner in the transportation division for more than 28 years before retiring in 1971. i

She was born in Laurens, S.C., and reared in Rock Hill, S.C., where she attended Winthrop College. She earned a bachelor's degree from Sweet Briar College in Virginia in 1922.

Mrs. Wilson was a member of the Marcia Burns Chapter of the National Society of the Daughters of the American Revolution and of St. Margaret's Episcopal Church in Washington.

Her husband, York Lowry Wilson, who had been a textile economist with the old Office of Price Administration, died in 1962.

Survivors include four sons, York Lowry Jr. of Aloha, Ore., Blackburn, of San Francisco, Oscar B., of Tampa, Fla., and Gaston de F., of Hyattsville; three daughters, Minerva W. Andrews and Suzanna W. Beckman, both of McLean, and Eleanor W. Yarbrough, of Great Falls, Va., 19 grandchildren and three great-grandchildren. A son, Alexander L. died in 1977.

The family suggests that expressions of sympathy be in the form of contributions to the Hospice of Northern Virginia in Arlington.