Ari Mikael Koivunen (born June 7, 1984) is the winner of the 2007 Finnish Idols competition. A resident of Lahti, Koivunen breezed into the finals after winning 86% of the public vote for his rendition of Billy Joel's Piano Man. On the first of March, 2007, Koivunen reserved himself a place in the second round of competition with his version of Deep Purple's Perfect Strangers.

Koivunen moved on to the third round of the competition on March 8th with his performance of the Iron Maiden classic The Evil That Men Do.

On the 15th of March, Koivunen made it into the fourth round of competition, singing the Whitesnake hit, Here I Go Again. Despite some criticism from the judges for singing only heavy metal songs in the finals, Koivunen was unperturbed. "I don't see any reason to consider what people might like, since it seems they like the same thing I do," said Koivunen. At the end of the evening, Koivunen, the six other Idols finalists, and three of the semifinalists were presented with gold records for their album Idols 2007, which sold over 15,000 copies in the two days after its release.

The fourth Idols final was held on March 22, and Koivunen chose to sing, in keeping with the week's theme, two songs by his own idols, the Led Zeppelin hit Rock and Roll and Hunting High and Low by the Finnish metal band Stratovarius.1 The judges, however, were not pleased with Koivunen's continuance of the heavy metal line, and gave him an unprecedented four negative reviews. The voting public was of a different opinion, as Koivunen again made it into the next round without being in danger of elimination.

The fifth Idols final was held on March 29, and Koivunen won over the judges completely with his version of the Broadcast ballad You Break My Heart. For his second song, Koivunen sang the Finnish hit Sielut iskee tulta by the heavy metal band Kilpi.1. With these performances, Koivunen made it to the Idols final which was held on April 6, 2007 in the Helsinki Ice Arena, where he won his fellow competitor Anna Abreu.

Prior to entering Idols, Koivunen won the Finnish Karaoke Championships in 2005, and placed third in the World Karaoke Championships the same year.