Robert Marshall may refer to:
Robert Marshall (magician), medieval magician's assistant allegedly involved in a plot to kill Edward II of England
Robert Marshall (Irish judge) (1695–1774)
Robert Marshall (New Brunswick politician) (1832–1904), businessman and politician in New Brunswick, Canada
Robert Marshall (dramatist) (1863–1910), Scots playwright
Robert Marshall (footballer) (1864–1924), Scottish footballer with Partick Thistle, Rangers, Scotland
Robert Marshall (cricketer, born 1869) (1869–1937), English cricketer
Robert Colin Marshall (1883–1962), Calgary mayor and Alberta MLA
Robert C. Marshall (1888–1972), American football and basketball coach
Robert George Marshall (1893-1957), American politician and businessman
Bob Marshall (wilderness activist) (1901–1939), American wilderness activist
Robert Marshall (cricketer, born 1912) (1912–1956), New Zealand cricketer
Robert L. Marshall (1913–2008), educationalist
Robert J. Marshall (1918–2008), American clergyman and religious leader
Sir Robert Marshall (civil servant) (1920–2000), British civil servant
Robert O. Marshall (1939–2015), American businessman charged with (and later convicted of) the contract killing of his wife, Maria
Robert G. Marshall (born 1944), Virginia politician and Member of the Virginia House of Delegates
Robert I. Marshall (1946–2024), American politician in Delaware
Robert W. Marshall (born 1959), American priest and bishop
Robert Neal Marshall (born 1960), American theatre and television actor
Robert Marshall (writer) (born 1960), American writer, critic and artist
Robert Marshall (snooker player) (born 1964), English snooker player
Robert Marshall (bowls) (born 1964), Scottish international lawn bowler
Róbert Marshall (born 1971), Icelandic politician