Cora Lucinda Pinkney, 86, a founder and past president of the Prince George's County Parent-Teacher Association (PTA) and a former substitute teacher in county schools, died Monday of cardiac arrest at her home in Brandywine.

Mrs. Pinkney, who was born in Brandywine, was president of the Prince George's County PTA for 29 years. She was also a founder of the Maryland PTA and a past president of the Maryland Congress of Parents and Teachers.

Her other civic work included service on the executive board of the Prince George's County Citizens Association.

She joined the county school system in the early 1920s and taught elementary school full time for about six years. From that time until she retired about 1970, she worked as a substitute teacher for the county.

Mrs. Pinkney was a member of Clinton United Methodist Church and did volunteer work for the National Conference of Christians and Jews. She was a past president of Church Women United in Southern Prince George's County and served as a delegate to the executive committee of Religious Heritage of America.

She was the widow of Sydney Pinkney, who died in 1977.

Survivors include a son, Alvin L. Pinkney of Washington; two daughters, Erma P. Green of Seat Pleasant, and Anne P. Prince of Clinton; five grandchildren, and six great-grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the Arthritis Foundation, metropolitan Washington chapter.