Under the non-credible environment, transmitting sensitive information such as plain text passwords is easy to lead to security issues of login of digital library. The paper proposes an improved solution based on a one-way Hash function, which uses information technology such as message digest and JavaScript, and sensitive information such as plain text passwords will be hashed for the fixed-length and single-effective “digital fingerprint” before entering the non-credible environment, so it can enhance present security of login of digital library.