Koshu Musha Nobori (甲州武者のぼり) are traditional warrior banners from the Koshu region (modern-day Yamanashi Prefe- cture), often displayed along-side koinobori (carp streamers) during Children's Day in Japan. These banners depict heroic samurai warriors, legendary figures, or battle scenes, symbolizing courage, strength, and a wish for boys to grow up brave and re- silient. The musha nobori are hand-painted or printed on fabric and are typically flown with koinobori to celebrate the martial spirit and virtues of the samurai, emphasizing both strength and protection in Japanese cultural traditions.