Samurai Executioner, known in Japan as Kubikiri Asa (首斬り朝?), is a 10-volume manga created by writer Kazuo Koike and artist Goseki Kojima, the same team that created the popular Lone Wolf and Cub series. The series was first serialized in Japan, from 1972-1976, arriving two years after Lone Wolf and Cub's start.

The story is set in the Edo period of feudal Japan. It revolves around Yamada Asaemon (山田 浅右衞門, Yamada Asaemon?), nicknamed Kubikiri-Asa (literally "Neck-chopper Asa", often transliterated as "Decapitator Asaemon"), a ronin who is responsible for testing new swords for the shogun. The character is based on a real-life line of sword-testers who served the Tokugawa Shogunate up to the early 19th century.[1] He is also frequently called upon to perform executions.

Many of the stories focus not on Asaemon, but on several of the people he meets in the course of his work. More often than not they are the stories of the criminals he executes, told as their last words before receiving the fatal stroke. As with Ogami Itto later, such encounters often give Asa pause for thought and reflection.

The Samurai Executioner series was published in English translation in the United States by Dark Horse Comics beginning in 2004. The series was completed with the tenth volume, released on May 26, 2006.

Each volume is written with historical accuracy, although the characters themselves are fictional. In the back of each book, Dark Horse has provided a glossary to help define the many Japanese terms used to keep the stories authentic.