A detailed technique of decapitation by the sword in the Middle Ages could be elucidated from the skulls with the upper cervical vertebrae of two males from Imakoji-nishi site, Kamakura, Kanagawa Pref., Japan, which dated back to the Nanbokucho or early Muromachi period, i. e. the latter half of the 14th century. The observations showed that in both males the sword cut deep into the 4th cervical vertebra from the posterior right side and came a short stop halfway in the vertebral column, followed by a secondary cut added to the 3rd cervical vertebra in a male to sever his head from the body. Old Japanese tradition said that the anterior skin of the neck of the convicted person should be left intact in decapitation. This seemed to indicate that the old Japanese saying and the real technique of beheading in the Middle Ages agreed with each other. In comparison with Iron Age specimens from Sutton Walls, Great Britain, it was suggested that the Japanese way of decapitation by the sword might be distinguishable from the old European by a primary clean but halfway cut deep into the neck from behind to lop the head.