Arnar Pétursson (born 12 March 1991) is an Icelandic long-distance runner. In 2018, he competed in the men's half marathon at the 2018 IAAF World Half Marathon Championships held in Valencia, Spain. He finished in 116th place. In 2019, he won the bronze medal in the men's 10,000 metres event at the 2019 Games of the Small States of Europe held Budva, Montenegro.