The Uygurs living in the southern part of Khan Tengri (Tianshan Mountains) established the Karakhanid Uygur Kingdom in 840 with the support of other Turkic clans, with Kashgar as its capital. In 934, during the rule of Satuk Bughra Khan, the Karakhanids embraced Islam, after which they continued to preserve their culture dominance in Central Asia. In this period hundreds of world-renowned Uygur scholars emerged and hundreds of valuable books were written. Among these works Kutatku Bilik, Divani Lugatit Turk and Atabetul Hakayik, are well known. Kutatku Bilik (The Knowledge Befitting a Ruler), was written in 1069 by Yusuf Has Hajip, Counsellor to the Khan. It is a unique example of a work that explains social, cultural, and political life of the Uygurs during this period. It also gives information about medical knowledge, as well as their customs. In this article we summarize some important parts of this huge work regarding hygiene