Sumarlidi Sigurdsson (died between 1014 and 1018) was jointly Earl of Orkney with his brothers Brusi and Einar Wry-Mouth following the death of their father, Sigurd Hlodvisson at the battle of Clontarf.
Sumarlidi is reported to have died in his bed. His death led to quarrels between Brusi and Einar over Sumarlidi's share of the islands.