Grace E. DeLong was born on April 12, 1890, in Cavalier County, North Dakota. She received her certificate to teach from the University of North Dakota in 1911 and graduated from UND in 1915 with degrees in liberal arts and education. DeLong taught home economics at various North Dakota and Minnesota schools until 1921 when she became the State Home Demonstration Leader of the North Dakota Agricultural College Extension Service.
DeLong was the State Home Economics program leader for 33 of her almost 40 years with NDAC Extension. In 1936, she became the first North Dakota recipient of the Epsilon Sigma Phi State Distinguished Service Award.
Grace DeLong died on February 8, 1981, in Fargo, North Dakota.