Viðarsson is an Icelandic surname. Notable people with the surname include:
Arnar Viðarsson (born 1978), Icelandic footballer, Brother of Bjarni and Davíð Bjarni Viðarsson (born 1988), Icelandic footballer, Brother of Arnar and Davíð Davíð Viðarsson (born 1984), Icelandic footballer, Brothher of Arnar and Bjarni Elliði Snær Viðarsson (born 1998), Icelandic handballer