Migration and Distribution (Information missing) The Kou surname is not ranked among the top 100 surnames in the Chinese Hundred Family Surnames in both the Chinese mainland and Taiwan. The Kou surname dates back to the Pre - Qin period. In every dynasty, the official position of Sikou was established, which was in charge of public security, criminal law, case adjudication, etc. Most of the Sikou clan were descendants of those who had served as Sikou. Later, the Sikou clan was simplified to the Kou clan. The origin of the Kou surname is the same as that of the Sikou clan. Most of the Kou clan evolved from the simplification of Sikou, and the Sikou clan originated from the official title in the Zhou Dynasty. The main ancestors of the Kou clan are Su Niansheng and Kang Shu, who served as Sikou in the Zhou Dynasty. In addition, some people with the Kou surname evolved from the Xianbei ethnic group. There was the Kouyin clan in the Xianbei ethnic group, and when they were sinicized, they adopted the character "Kou", which has a similar pronunciation, as their surname.