The invention discloses text message security technology, and belongs to the field of text message security, which is an important complement for well overcoming the defects of the text message security in the mechanic password and electronic encryption technology. In the technology, some simple and general symbols are regularly recombined into new symbols for expressing words and phrases to form a password. In Chinese, a password is set by using substitution symbols of initials, finals and roots of a Chinese character to encrypt each character in a file and the password security is greater than 2,626*3,434 times. In English, a password is set by using substitution symbols of the letters of a word, the password security is greater than 2,626 times and a text message can be provided with numerous layers of passwords by using the password technology. The passwords for each person can be unique, be changed without limitation, serve as shorthand and independent language, be input and output on common computers, manually encrypt text messages, serve as translation software for encrypting the text messages on electronic devices, serve as the future programming language for encrypting each program code, and be largely used for confidential files in politics, military, scientific research institutions and commercial enterprises and for private text messages of ordinary people.