Rúnar Már Sigurjónsson (full name Rúnar Már Sigurlaugarson Sigurjónsson,though the matronymic 'Sigurlaugarson' is usually shortened to just "S.") is an Icelandic footballer who plays as a midfielder for GIF Sundsvall. He made his debut for the Icelandic national team against Andorra in late 2012.

Rúnar played a few games for the youth sides of Iceland, eight games in total. After a good 2012 season, during which he scored 7 goals, he was picked for the senior squad for a FIFA World Cup 2014 qualifier match against Switzerland in October 2012 but was an unused substitute. A month later he started in a friendly match against Andorra, scoring the second goal of the game on his debut, a 2-0 win for Iceland.

He was selected for EURO 2016.