With the arrival of the information age and much more important information systems and communication in human everyday life, necessity immunization information and communication strategy were also raised. The easiest way to meet this necessity is conventional encryption algorithms. Encryption is a right tool for data protection in an unsecure channel. To this end, from two-method symmetric key encryption and public-key cryptography are used. In this paper we examine text cryptography, one of the most important topics in cryptography. A unique attribute of this kind of encryption has been of interest to many researchers in this field. This paper, considering the symmetric encryption algorithm, provides a text encryption algorithm using a 128-bit key. The proposed algorithm uses a 128-bit key, the text data using the XOR operator to convert the encrypted information. Therefore, the aim of this method is to provide a convenient method for symmetrically encrypting data not to be easily decoded, and finally, the results of the tests show that the proposed method is better in terms of security and speed of execution.