The invention provides a novel image 
encryption method based on correlation between chaos and 
plaintext. The method comprises the steps: carrying out row and column updating of a 
plaintext image A, and obtaining a processed image E; employing the modular operation of a 
gray level 256, changing the pixel sum of the image through the modular operation between rows and the modular operation between columns, and breaking the strong correlation between the adjacent rows and the adjacent columns of an original 
plaintext image; enabling the pixel sum s of the image E to serve as the feature of the image, extracting the feature of the image, participating the generation of a key 
stream, carrying out the second layer 
encryption through scrambling 
encryption, and obtaining an image Q; and solving a problem that a conventional 
algorithm employs the same key 
stream while encrypting different images. Through the gray value 
diffusion of the image, the method builds the 
mutual influence between two adjacent pixels, and a secret key directly participates in the output of a 
ciphertext image. In order to achieve an 
avalanche effect, the 
mutual influence between two adjacent pixels is built through the key 
stream. Meanwhile, a second group of secret keys are designed to participate in the output of the 
ciphertext image, thereby achieving the third layer encryption.