A method for processing a speech/audio signal, wherein the method comprises: receiving a bitstream, and decoding the bitstream, to obtain a speech/audio signal; determining a first speech/audio signal according to the speech/audio signal, wherein the first speech/audio signal is a signal, whose noise component needs to be reconstructed, in the speech/audio signal; determining a sign of each sample value in the first speech/audio signal and an amplitude value of each sample value in the first speech/audio signal; determining an adaptive normalization length; determining an adjusted amplitude value of each sample value according to the adaptive normalization length and the amplitude value of each sample value; and determining a second speech/audio signal according to the sign of each sample value and the adjusted amplitude value of each sample value, wherein the second speech/audio signal is a signal obtained after the noise component of the first speech/audio signal is reconstructed; wherein determining an adjusted amplitude value of each sample value according to the adaptive normalization length and the amplitude value of each sample value comprises: calculating, according to the amplitude value of each sample value and the adaptive normalization length, an average amplitude value corresponding to each sample value, and determining, according to the average amplitude value corresponding to each sample value, an amplitude disturbance value corresponding to each sample value; and calculating the adjusted amplitude value of each sample value according to the amplitude value of each sample value and according to the amplitude disturbance value corresponding to each sample value; wherein calculating the adjusted amplitude value of each sample value according to the amplitude value of each sample value and according to the amplitude disturbance value corresponding to each sample value comprises: subtracting the amplitude disturbance value corresponding to each sample value from the amplitude value of each sample value, to obtain a difference between the amplitude value of each sample value and the amplitude disturbance value corresponding to each sample value, and using the obtained difference as the adjusted amplitude value of each sample value; wherein calculating, according to the amplitude value of each sample value and the adaptive normalization length, an average amplitude value corresponding to each sample value comprises: determining, for each sample value and according to the adaptive normalization length, a subband to which the sample value belongs; and calculating an average value of amplitude values of all sample values in the subband to which the sample value belongs, and using the average value obtained by means of calculation as the average amplitude value corresponding to the sample value. receiving a bitstream, and decoding the bitstream, to obtain a speech/audio signal; determining a first speech/audio signal according to the speech/audio signal, wherein the first speech/audio signal is a signal, whose noise component needs to be reconstructed, in the speech/audio signal; determining a sign of each sample value in the first speech/audio signal and an amplitude value of each sample value in the first speech/audio signal; determining an adaptive normalization length; determining an adjusted amplitude value of each sample value according to the adaptive normalization length and the amplitude value of each sample value; and determining a second speech/audio signal according to the sign of each sample value and the adjusted amplitude value of each sample value, wherein the second speech/audio signal is a signal obtained after the noise component of the first speech/audio signal is reconstructed; calculating, according to the amplitude value of each sample value and the adaptive normalization length, an average amplitude value corresponding to each sample value, and determining, according to the average amplitude value corresponding to each sample value, an amplitude disturbance value corresponding to each sample value; and calculating the adjusted amplitude value of each sample value according to the amplitude value of each sample value and according to the amplitude disturbance value corresponding to each sample value; subtracting the amplitude disturbance value corresponding to each sample value from the amplitude value of each sample value, to obtain a difference between the amplitude value of each sample value and the amplitude disturbance value corresponding to each sample value, and using the obtained difference as the adjusted amplitude value of each sample value; determining, for each sample value and according to the adaptive normalization length, a subband to which the sample value belongs; and calculating an average value of amplitude values of all sample values in the subband to which the sample value belongs, and using the average value obtained by means of calculation as the average amplitude value corresponding to the sample value.