"Samurai Blue" is a catchphrase thought up by the Japan Football Association (JFA) to support the Japanese team at the 2006 FIFA World Cup Germany. Several candidate phrases were put forward, but "Samurai Blue" was the overwhelming choice of fans in a January poll.

The phrase combines the word for Japan's ancient warriors, samurai, which has become widely known around the world through such media as the movie Last Samurai, with the color of Japan's national team shirts, blue. "Samurai Blue" has connotations of battling with pride, a sense of fair play, and a strong desire for victory.

In the buildup to the World Cup, blue flags have been distributed to fans at soccer matches and events all over the country, while some buses have been wrapped in blue to show support for the Japanese team. A giant tent named Samurai Blue Park has opened in Yokohama to serve as an official fan base. Meanwhile, the JFA has called on people nationwide to wear something blue on days when Japan has a match, so as to spread the "Samurai Blue" spirit throughout the country. (June 14, 2006)