An encryption method includes: converting a section of express information into a binary sequence, grouping the binary sequence into a plurality of group data, and aligning each group data into an information matrix; converting the information matrix into a corresponding a basic group information matrix; randomly choosing a reference DNA sequence from a gene library, and aligning the reference DNA sequence into a basic group transition matrix, using the basic group transition matrix to convert the basic group information matrix into an encrypted information matrix, and exploding the encrypted information matrix to obtain a basic group information sequence; generating a primer for the basic group information sequence, and adding the primer before and behind the primer generator to obtain a completed DNA sequence; and synthesizing a DNA matter based on the completed DNA sequence.