Abstract:Algebraic Immunity has been considered as one of significant cryptographic properties for Boolean functions. In order to resist algebraic attack, high algebraic immunity is necessary for those Boolean functions used in symmetric cipher algorithms. Based on “orbit exchange” technique, this research presents a construction of rotation symmetric Boolean functions with the maximum algebraic immunity on even number of variables. These functions have strong resistance against algebraic attacks. These functions also have much better nonlinearity and optimal algebraic degree.