Arnarson is an Icelandic masculine surname. Notable people with the surname include:
Ingólfr Arnarson (c. 849–c. 910), first permanent Nordic settler of Iceland Örn Arnarson (born 1981), Icelandic swimmer Ottó P. Arnarson, member of Týr (band), a folk metal band from the Faroe Islands Björgvin Arnarson (born 2005), actor
See also Arnara