Satellite image data encryption and decryption method and system

The invention provides a satellite image data encryption and decryption method and system. The method comprises the steps that the encryption process comprises the steps that an encryption key is set; setting encryption times; the method comprises the following steps: splitting satellite image data according to bytes, taking bytes of a predefined number as a data segment, and forming new data in a data segment format by using the satellite image data; circularly encrypting the new data in the data segment format according to the data segment by using an encryption method by applying the encryption key and the encryption times to obtain a ciphertext; the decryption process comprises the following steps: setting a decryption key; setting decryption times; and circularly decrypting the ciphertext by using a decryption method by applying the decryption key and the decryption times to obtain a plaintext. According to the scheme provided by the invention, segmented encryption is carried out on the satellite image d