Herbert Spencer Gasser (July 5, 1888 – May 11, 1963) was an American physiologist, and recipient of the Nobel Prize for Physiology or Medicine in 1944 for his work with action potentials in nerve fibers while on the faculty of Washington University in St. Louis, awarded jointly with Joseph Erlanger.
 

Glasser was born in Platteville, Wisconsin, the son of Jane Elisabeth (née Griswold) and Herman Gasser, a physician. His father was from Dornbirn in the Austrian province Vorarlberg, and his mother was of New England Yankee and German Russian ancestry. He received his M.D. degree from Johns Hopkins University in Baltimore in 1915. During World War I he was engaged in chemical warfare research at American University. He was professor of physiology at the Rockefeller Institute for Medical Research.