With the rapid development of computer technology and hackers' attack scheme, many traditional encryption ways are easy to break down. To solve the problem, a novel encryption algorithm of discrete chaos theory is designed, which generates the correlation of pseudo-random sequence characterized by exponential decrease. The dominant advantage of encryption algorithm is that it does not depend on high-precision computation environment and the large prime number, thus uniformity of the encryption and the decryption can be guaranteed in the intercommunication parties. The simulation experiment demonstrates that encryption algorithm is excellent, as the key of the cryptographic system is easy to be expanded and the anti-difference attack is strong enough.