The 9th International Conference on Cryptology and Network Security (CANS 2010) was held in Kuala Lumpur, Malaysia during December 12-14, 2010. The conference was co-organized by the Multimedia University (MMU), Malaysia, and Universiti Tunku Abdul Rahman (UTAR), Malaysia. The conference received 64 submissions from 22 countries, out of which 21 were accepted after a careful and thorough review process. These proceedings also contain abstracts for two invited talks. All submissions were reviewed by at least three members of the Program Committee; those authored or co-authored by Program...