A user system incorporating a voice instruction recognition processing portion and a transmission control portion is connected through a communication line to a center system incorporating a reception control portion, a voice instruction recognition processing portion and an output control portion. Processing for obtaining a voice instruction content based on a waveform analysis result of the voice instruction is shared by voice instruction recognition processing portions. This share prevents decrease of a recognition rate occurred in the case of disposing a voice analysis recognition processing function only on the center system. The share also eliminates waiting time for transfer of lexical grammar data generated in the case of disposing the voice analysis recognition processing function only on the user system. Further, a processing load of the user system is decreased. Thus, high recognition capability is obtained even with voice input from a user terminal low in power consumption.