An audio signal coding method, wherein the method comprises: obtaining a frequency domain signal according to an input audio signal; allocating predetermined bits to the frequency domain signal according to a predetermined allocation rule, wherein a majority of bits in the predetermined bits are allocated to a low frequency band signal in the frequency domain signal; adjusting the bit allocation for the frequency domain signal when a highest frequency of the frequency domain signal to which bits are allocated is greater than a predetermined value; and coding the frequency domain signal according to the bit allocation for the frequency domain signal; wherein the step of adjusting the bit allocation for the frequency domain signal comprises: reducing the number of bits allocated to a frequency band to which a majority of bits are allocated in the frequency domain signal, and increasing the number of bits allocated to the highest frequency to which bits are allocated and to a frequency domain signal near the highest frequency, wherein the highest frequency of the frequency domain signal to which bits are allocated is a frequency f 2, the frequency band to which a majority of bits are allocated is in a range of 0 kHz to a frequency f 1, and the frequency domain signal near the highest frequency is in a range of f 1 to f 2 obtaining a frequency domain signal according to an input audio signal; allocating predetermined bits to the frequency domain signal according to a predetermined allocation rule, wherein a majority of bits in the predetermined bits are allocated to a low frequency band signal in the frequency domain signal; adjusting the bit allocation for the frequency domain signal when a highest frequency of the frequency domain signal to which bits are allocated is greater than a predetermined value; and coding the frequency domain signal according to the bit allocation for the frequency domain signal; wherein the step of adjusting the bit allocation for the frequency domain signal comprises: reducing the number of bits allocated to a frequency band to which a majority of bits are allocated in the frequency domain signal, and increasing the number of bits allocated to the highest frequency to which bits are allocated and to a frequency domain signal near the highest frequency, wherein the highest frequency of the frequency domain signal to which bits are allocated is a frequency f 2, the frequency band to which a majority of bits are allocated is in a range of 0 kHz to a frequency f 1, and the frequency domain signal near the highest frequency is in a range of f 1 to f 2 reducing the number of bits allocated to a frequency band to which a majority of bits are allocated in the frequency domain signal, and increasing the number of bits allocated to the highest frequency to which bits are allocated and to a frequency domain signal near the highest frequency, wherein the highest frequency of the frequency domain signal to which bits are allocated is a frequency f 2, the frequency band to which a majority of bits are allocated is in a range of 0 kHz to a frequency f 1, and the frequency domain signal near the highest frequency is in a range of f 1 to f 2