Eino Ilmari “Illu” Juutilainen (21 February 1914 – 21 February 1999) was a fighter pilot of the Ilmavoimat (Finnish Air Force), and the top scoring non-German fighter pilot of all time. This makes him the top flying ace of the Finnish Air Force, leading all Finnish pilots in score against Soviet aircraft in World War II (1939–40 and 1941–44), with 94 confirmed aerial combat victories in 437 sorties. He himself claimed 126 victories. He achieved 34 of his victories while flying the Brewster Buffalo fighter.

Juutilainen was born in Lieksa, and died in Tuusula.

Juutilainen was the top scoring Finnish fighter pilot. He flew Fokker D.XXI, Brewster Buffalo, and Messerschmitt Bf 109 fighters. He was one of only four people to twice receive the highest Finnish military decoration, the Mannerheim Cross, and is considered the highest scoring non-German ace of all time. Juutilainen finished the war without a single hit to his plane from enemy fighter airplanes (once he was forced to land after a friendly anti-aircraft gun fired at his Bf 109). Like Japanese fighter ace Saburo Sakai, Juutilainen never lost a wingman in combat.