A method for microphone selection, characterized in that the method is applied in a mobile device having at least two microphones and comprises: transmitting, by using an ultrasonic transmitter of the mobile device, first ultrasonic waves within an audio-enclosed test box, wherein the first ultrasonic waves are transmitted with a predefined transmission strength and in different frequencies selected from a predefined frequency range; acquiring, by using each of the at least two microphones adapted to receive second ultrasonic waves resulting from the reflection of the first ultrasonic waves within the test box, frequency response values of the second ultrasonic waves received by each of the at least two microphones; and wherein for each second ultrasonic wave resulting from the reflection of a respective first ultrasonic wave of a respective frequency selected from the predefined frequency range, a frequency response value of the second ultrasonic wave received by each of the at least two microphones is the highest amplitude received by the microphone within periods of the second ultrasonic wave of the respective frequency, the method further comprising: acquiring a highest frequency response value for each of the at least two microphones by comparing the frequency response values of the second ultrasonic waves of the different frequencies received by the microphone and determining a highest frequency response value as the highest frequency response value of the microphone; determining the highest frequency response value for each of the at least two microphones as a standard frequency response value of the microphone; and selecting the microphone between the at least two microphones which has the highest standard frequency response value as the microphone configured for receiving ultrasonic waves during subsequent operations of the mobile device. transmitting, by using an ultrasonic transmitter of the mobile device, first ultrasonic waves within an audio-enclosed test box, wherein the first ultrasonic waves are transmitted with a predefined transmission strength and in different frequencies selected from a predefined frequency range; acquiring, by using each of the at least two microphones adapted to receive second ultrasonic waves resulting from the reflection of the first ultrasonic waves within the test box, frequency response values of the second ultrasonic waves received by each of the at least two microphones; and wherein for each second ultrasonic wave resulting from the reflection of a respective first ultrasonic wave of a respective frequency selected from the predefined frequency range, a frequency response value of the second ultrasonic wave received by each of the at least two microphones is the highest amplitude received by the microphone within periods of the second ultrasonic wave of the respective frequency, the method further comprising: acquiring a highest frequency response value for each of the at least two microphones by comparing the frequency response values of the second ultrasonic waves of the different frequencies received by the microphone and determining a highest frequency response value as the highest frequency response value of the microphone; determining the highest frequency response value for each of the at least two microphones as a standard frequency response value of the microphone; and selecting the microphone between the at least two microphones which has the highest standard frequency response value as the microphone configured for receiving ultrasonic waves during subsequent operations of the mobile device. acquiring a highest frequency response value for each of the at least two microphones by comparing the frequency response values of the second ultrasonic waves of the different frequencies received by the microphone and determining a highest frequency response value as the highest frequency response value of the microphone; determining the highest frequency response value for each of the at least two microphones as a standard frequency response value of the microphone; and selecting the microphone between the at least two microphones which has the highest standard frequency response value as the microphone configured for receiving ultrasonic waves during subsequent operations of the mobile device.