A mobile communication terminal interacts with a digital hearing aid and a wireless hearing aid uses the mobile communication terminal. When a user having the mobile communication terminal interworking with the digital hearing aid operates the hearing aid, an amplification function suitable for auditory characteristics of the user is performed. That is, when auditory information of the user is sent to the terminal, the terminal adjusts an amplification gain to prevent the acoustic shock by measuring an environmental signal. The terminal computes an environment profile by analyzing the measured environmental signal and auditory information of the user sent from the hearing aid and automatically adjusts a non-linear amplification level according to a user environment by sending the environment profile to the hearing aid.