The invention provides a data processing system for voice communication. The data processing system for voice communication comprises a first output module, a first prompt module, a first safety chip, a second output module, a second safety chip, a second play module and a second prompt module. The first output module is used for outputting a first authorization code. The first prompt module is used for prompting reading on the first authorization code. The first safety chip is used for obtaining a reading result of the first authorization code and obtaining a first voice message; the first voice message is encrypted, so that first encrypted data are obtained, and the first encrypted data are sent; after a first confirmation instruction is obtained, the encryption and decryption operation on voice communication is started. The second output module is used for outputting a second authorization code. The second safety chip is used for receiving the first encrypted data, decrypting the first encrypted data and obtaining first decrypted data. The second play module is used for playing the first encrypted data. The second prompt module is used for prompting confirmation on the first encrypted data. The second safety chip is further used for starting the encryption and decryption operation on voice communication after receiving a second confirmation instruction.