Óttarsson is a family name. It may refer to:

• Hallfreðr Óttarsson (ca. 965 - ca. 1007), also known as Hallfreðr vandræðaskáld (Troublesome Poet) Icelandic skald (poet)
• Ásbjörn Óttarsson (born 1962), Icelandic politician
• Guðlaugur Kristinn Óttarsson (born 1954), Icelandic guitar player, engineer, mathematician, inventor, lecturer

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