The present disclosure provides a system and a method for voice prompt of a third-party call. The system includes a contact identification module, a hands-free control module and a voice broadcast module. The contact identification module is for identifying whether a third-party incoming call number exists in an address book of a communication device. The hands-free control module is for extracting a current call status when a third-party call dials in to help judge whether the current call is in hands-free mode. The voice broadcast module is for voice broadcasting information of the incoming call according to the identification result of the contact identification module when the current call is in hands-free mode. The present system could broadcast the information of the third-party incoming call without breaking off the current call so that prevents missing important content of the current call as well as an important incoming call.