In view of the security risks of electronic archives in the process of preservation, a fast encryption method of electronic archives based on ciphertext strategy is proposed. The archive storage process is analyzed from two aspects of new addition and update, and a secure channel is established by using quantum communication technology to create a secure channel environment for archive and key transmission; a fast encryption model is constructed by using a ciphertext strategy, and basic information such as the number of starting points of a linear process and security parameters is set; a public parameter and a process access structure are taken as inputs, and a mapping function is determined to generate a ciphertext; The input information and composition elements of the key generation algorithm are selected to obtain the encryption private key; the ciphertext and the private key are taken as the input, the starting point secret is calculated, the final plaintext is calculated through the recursive operation, and the fast encryption is completed. The experimental results show that the encryption speed of this method is fast, the generated ciphertext is short, and the encrypted document has strong scrambling property.