The invention relates to a QR two-dimensional code 
binary image partition-based key-varying 
chaotic encryption method. The method comprises the following steps that: 1), a traditional logistic 
chaotic mapping 
encryption algorithm is improved in a manner that an auxiliary key is added such that a new initial value x0 can be formed; 2), an original QR-code 
binary image is partitioned, and the total number of sub-region images of which the pixel is 1 is calculated, and therefore, the initial values of random keys of sub-blocks are formed; and 3), the auxiliary key and the random key are combined with partition 
encryption technology, such that QR code 
binary image partition-based key-varying 
chaotic encryption and decryption algorithms can be realized. With the QR two-dimensional code binary image partition-based key-varying 
chaotic encryption method adopted, random variation of keys can be realized; 
key space and key paths can be expanded; the reliability and security of encryption can be enhanced; a requirement for QR code 
information confidentiality in storage and transmission can be satisfied; and at the same time, an encryption effect, encryption speed and 
cracking difficulty are further improved. The QR two-dimensional code binary image partition-based key-varying 
chaotic encryption method of the invention is advantageous in convenience, practicability, safety and reliability.