Talk assistive system is an application based on speech synthesizer that has been used by mute people to communicate to other people. Speech synthesizer is a system which use text-to-speech to convert inputted word or sentence into sound output. The final project is to try implement speech synthesizer on mobile devices and use Indonesian language as working language because this system is mostly available in form of non-mobile hardware and use foreign language as working language. In the application of this system, the user choose one word type category as first word and inputs it into text sentence box. After first word input, the user can choose a new word type category as second word and forth to be inputted. After the user finish input the sentence, he can push the play button and the sound will come in form of inputted sentence. Talk Assistive System is already created and then tested in two groups of user, which are group of mutely student from deaf special school and mute adult group. The overall result shows that Talk Assistive System implementation has reached 86.67% success rate.