Viðarsdóttir is an Icelandic patronymic surname, literally meaning "daughter of Viðar". Notable people with the name include:
Ásdís María Viðarsdóttir (born 1993), Icelandic singer and songwriter Elísa Viðarsdóttir (born 1991), Icelandic footballer Margrét Lára Viðarsdóttir (born 1986), Icelandic footballer Ólína Guðbjörg Viðarsdóttir (born 1981), Icelandic footballer