Harold David Harrington (March 14, 1903 – January 22, 1981) was an American botanist who specialized in flora of Colorado and the Rocky Mountains.

With his wife and fellow botanist Edith, he traveled around the United States, Europe, and Pacific, bringing back botanical photographs for use in teaching.

He published 17 books while at CSU, where the majority of his collection of specimens are kept as part of the university's herbarium that he had previously curated.

[1] Due to financial strains spurred by the Great Depression, Harold and his older brother Elbert alternated years in college so that one could work while the other was in school.

[2] Harrington's book remains an authoritative text on Colorado's flora and one in 30 of its entries were the first time a plant was recorded in the state.

Edith, who aided in collecting specimens and preparing her husband's publications, hand-typed the 1954 book and called it "her small way" of helping.

[3][2] The Harringtons also traveled, visiting Europe in 1964 and taking photographs of various plants for educational use back on the Front Range.

Their travels led them to visit every state in the continental U.S.[3] During trips to collect specimens with students, he would play the ukulele at the campfire after the day's work.

[8] Edith created the Harold David Harrington Graduate Fellowship at CSU in his memory to fund students in the field of plant taxonomy.

[10] Maurer helped fund the publication Flora of Colorado by Jennifer Ackerfield,[10] the CSU herbarium's curator.