The present invention relates to a method and an apparatus for processing a signal, which are used for effectively reproducing an audio signal, and more particularly, to a method and an apparatus for processing a signal, which are used for implementing binaural rendering for reproducing multi-channel or multi-object audio signals in stereo with a low calculation amount.To this end, provided are a method for processing an audio signal including: receiving multi-audio signals including multi-channel or multi-object signals; receiving truncated subband filter coefficients for filtering the multi-audio signals, the truncated subband filter coefficients being at least a portion of subband filter coefficients obtained from a binaural room impulse response (BRIR) filter coefficient for binaural filtering of the multi-audio signals, and the lengths of the truncated subband filter coefficients being determined based on filter order information obtained by at least partially using characteristic information extracted from the corresponding subband filter coefficients; and filtering the subband signal by using the truncated subband filter coefficients corresponding to each subband signal of the multi-audio signals and an apparatus for processing an audio signal using the same.