The invention provides an AES (Advanced Encryption Standard)-based encryption method and device. The method comprises the following steps: firstly, acquiring to-be-encrypted data and a preset key of astandard AES algorithm; secondly, generating a digit number r of cyclic shift, converting the to-be-encrypted data into a first plaintext square matrix, and converting the preset key into a first keysquare matrix; thirdly, cyclically shifting the column of the first plaintext square matrix leftwards by r digits to acquire a second plaintext square matrix subjected to cyclic leftward shifting, and cyclically shifting the column of the first key square matrix leftwards by r digits to acquire a second key square matrix subjected to cyclic leftward shifting; fourthly, performing AES encryption on the second plaintext square matrix based on the second key square matrix to acquire a first output square matrix, wherein during the performing of the AES encryption, a differential energy consumption analysis-resistant side channel protection method is combined; and finally, cyclically shifting the first output square matrix rightwards by r columns to acquire a second output square matrix, wherein the second output square matrix is used as an encryption result. The AES-based encryption method achieves a technical effect of enhancing the side channel attack resistance.