Norman Henry Giles (August 6, 1915 – October 16, 2006) was an American microbial geneticist who studied mutations of Neurospora crassa.

Norman H. Giles was a pioneer in genetics research.

In 1972 Giles accepted a professorship at the University of Georgia where he established an active program in genetics that in 1980 became the Department of Genetics.

Giles made important scientific contributions in the areas of intragenic complementation, gene conversion and analysis of gene clusters.

His early work on intragenic complementation led to the insight that complementation between allelic mutants is of widespread occurrence and likely involves interactions occurring in the cytoplasm between defective gene products, that is between polypeptides.