Harðardóttir is an Icelandic surname, meaning daughter of Hörður. Notable people with the surname include:
Eygló Harðardóttir (born 1972), Icelandic politician Manuela Ósk Harðardóttir (born 1983), Icelandic beauty queen and model Oddný Guðbjörg Harðardóttir (born 1957), Icelandic politician
See also Harðarson, masculine equivalent