A Practical One Way Hash Algorithm based on Matrix Multiplication International Journal of Computer Applications © 2011 by IJCA Journal Number 2 - Article 7 Year of Publication: 2011 Authors: Mohammed Abu Taha Mousa Farajalla Radwan Tahboub 10.5120/2859-3677 {bibtex}pxc3873677.bib{/bibtex} Abstract It is well known that Hash algorithm works in one way, and it cannot be reversed. We can build a new algorithm by using Hill cipher technique .Since its invention in 1929, Hill cipher algorithm which is one of the most famous symmetric cryptosystems .Hill cipher requires the inverse of the key matrix for decryption. This inverse not always exists, so we can use non-invertible matrices to propose a model for our new hash algorithm, and we proof the four requirements 1 / 3