Robert S. Murphy (October 18, 1861 – June 24, 1912) was an American lawyer and politician who served as the ninth Lieutenant Governor of Pennsylvania from 1907 to 1911. A Republican, Murphy was born in Louisville, New York, but spent most of his childhood in the area of Portland, Maine, where his father, Francis Murphy, was a temperance evangelist. Murphy died suddenly of apoplexy at his home in Overbrook, Pittsburgh, at the age of 51.