Thomas or Tom Duffy may refer to:
Thomas Duffy (VC) (1825–1868), Irish recipient of the Victoria Cross in 1857 Thomas A. Duffy (1906–1979), New York politician and judge Thomas C. Duffy (born 1955), American composer and conductor of the Yale University Concert Band Thomas F. Duffy (born 1955), American actor Thomas J. Duffy, American designer/craftsman Thomas T. Duffy (1835–?), American politician Tom Duffy (hurler) (1894–1989), Irish hurler Tom Duffy (rugby league) (born 2003), Australian rugby league Tom Duffy (ringmaster) (1929–2022), Irish circus performer and ringmaster Tom Duffy's Circus
See also Thomas Gavan-Duffy (1867–1932), Irish trade unionist and politician