Halldórsdóttir is an Icelandic surname, meaning daughter of Halldór. Notable people with the surname include:
Elínborg Halldórsdóttir (born 1962), Icelandic musician and painter Guðný Halldórsdóttir (born 1954), Icelandic film director and screenwriter Hafrún Rakel Halldórsdóttir (born 2002), Icelandic footballer Kolbrún Halldórsdóttir (born 1955), Icelandic politician Kristín Halldórsdóttir (1939–2016), Icelandic politician and journalist