McHarg is a surname. Notable people with the surname include:
Alastair McHarg (born 1944), Scottish rugby union player
Ian McHarg (1920–2001), Scottish architect
Marilyn McHarg, member of the Canadian section of Médecins Sans Frontières (MSF)
Rodger McHarg (born 1947), New Zealand cricket umpire
Scott McHarg (born 1974), Scottish football player
Cameron McKenzie-McHarg (born 1980), Australian rower