Robert M. Hardy, 83, founder and president of the old Nation-Wide Food Stores Inc., once one of the largest food cooperatives in the Washington area, died Tuesday in a Venice, Fla., hospital after a heart attack.

Mr. Hardy, who was born in Clinton and grew up on a farm there, founded Nation-Wide in 1934. He remained its president until 1955, when it was merged with District Grocery Stores Inc., another cooperative. He was general manager of District until 1957, when he retired.

Mr. Hardy worked on his father's farm after graduating from Surrattsville High School. In 1926, he started a family grocery store in Meadows, now the site of Andrews Air Force Base. He operated the grocery as well as heading Nation-Wide until the construction of Andrews forced the closing of the grocery early in World War II.

Mr. Hardy served in France with the 29th Infantry Division during World War I.

In 1920 he married the former Hazel Cleo Dray. She died in 1956. Mr. Hardy married Violette Lerner in 1960 and the couple moved to Venice, Fla.

Mr. Hardy was the superintendent of the Sunday school of the Bell's Methodist Church in Camp Springs, Md., for more than 25 years. When he retired in the early 1950s, he was made superintendent emeritus.

He also was a worthy patron of the Upper Marlboro chapter of the Eastern Star, a 32nd degree Mason, a Shriner of the Scottish Rite Almas Temple, a member of the College Park Rotary Club, a founder and first president of the Southern Prince George's Rotary Club, a founder and past president of the Grocery Wheels of Washington, a trade organization, and a member of the Terrapin Club at the University of Maryland. He served on the Prince George's County rationing board during World War II.

Survivors include his wife, of the home in Venice; two daughters, Mary Tippett, of Tampa, Fla., and Bea Turner, of College Park; two sons, George D. and Walter L., both of College park; three sisters, Eva Carrico and Patsy Hartman, both of Suitland, and Louise Victor, of Orlando, Fla.; eight grandchildren and one great-granddaughter.

The family suggests that expressions of sympathy be in the form of contributions to the Heart Fund or to the University of Maryland Educational Foundation, College Park, Md.