Henry Gardiner Ferguson was an American geologist with the United States Geological Survey (USGS). He worked primarily in Nevada and was a pioneer in the geology of the central Great Basin, producing many publications, including multiple USGS geological maps of central Nevada.
Ferguson was a lifelong friend and colleague of Levi Noble, a mentor to Ralph Roberts, and worked extensively with Siemon Muller.
Along with his wife Alice Ferguson, he helped found the Moyaone Reserve community in Accokeek, Maryland.