The emergence of quantum computer will threaten the security of existing public-key cryptosystems,including the Die Hellman key exchange protocol,encryption scheme and etc,and it makes the study of resistant quantum cryptography very urgent.This motivate us to design a new key exchange protocol and encryption scheme in this paper.Firstly,some acknowledged mathematical problems was introduced,such as ergodic matrix problem and tensor decomposition problem,the two problems have been proved to NPC.From the computational complexity prospective,NPC problems have been considered that there is no polynomial time quantum algorithm to solve them.From the algebraic structures prospective,noncommutative cryptography has been considered to resist quantum.The matrix and tensor operator we adopted also satisfied with this noncommutative algebraic structures,so they can be used as candidate problems for resisting quantum from perspective of computational complexity theory and algebraic structures.Secondly,a new problem was constructed based on the introduced problems in this paper,then a key exchange protocol and a public key encryption scheme were proposed based on it.Finally the security analysis,efficiency,recommended parameters,a simple instance and etc.were also been given.The two schemes has the following characteristics,provable security,security bits can be scalable,to achieve high efficiency,quantum resistance,and etc.