The invention provides a decoding apparatus and a decoding method for decoding corded data obtained by encoding each of a scale value and a spectrum value of frequency domain audio signal data to output an audio signal. The decoding apparatus includes a unit configured to decode and inversely quantize the coded data to obtain the frequency domain audio signal data, a unit configured to compute from the coded data one of the number of scale bits composed of the number of bits corresponding to the scale value of the coded data and the number of spectrum bits composed of the number of bits corresponding to the spectrum value of the coded data, a unit configured to estimate a quantization error of the frequency domain audio signal data based on one of the number of scale bits and the number of spectrum bits of the coded data, a unit configured to compute a correction amount based on the estimated quantization error and correct the frequency domain audio signal data obtained by the frequency domain data obtaining unit based on the computed correction amount, and a unit configured to convert the corrected frequency domain audio signal data into the audio signal.