Francis Hugh Adam Marshall, CBE, FRS (11 July 1878, High Wycombe – 5 February 1949, Cambridge) was a British physiologist. He was elected a Fellow of the Royal Society in 1920. He was an early researcher into the science of biological reproduction. His 1910 text The physiology of reproduction was influential. Marshall was awarded the CBE in 1933, the Croonian Lecture in 1936 and, in 1940, the Royal Medal by the Royal Society. Marshall's presence at the University of Edinburgh is cited as one of the reasons that the Institute of Animal Genetics was established there in the 1910s. The University of Edinburgh gave him an honorary Doctor of Laws degree in 1939. He died of appendicitis in 1949.
He graduated from Christ's College, Cambridge (college of the University of Cambridge) in 1890, and was a fellow at Christ's from 1909 to 1949.