A decoding apparatus comprising: a receiving section adapted to receive first encoded information and second encoded information, the first encoded information being generated in a coding apparatus and obtained by encoding a low frequency band of an input signal to be encoded in the coding apparatus equal to or lower than a predetermined frequency, and the second encoded information being generated in the coding apparatus and obtained by dividing a high frequency band of the input signal higher than the predetermined frequency into N subbands, where N is an integer greater than 1, searching for a part of a first decoded signal most similar to a spectrum of the first subband from the N subbands based on the input signal or the first decoded signal, and searching for a part of the decoded signal most similar to a spectrum of each next subband using the search result from its preceding subband, the first decoded signal being obtained by decoding the first encoded information in the coding apparatus; a first decoding section adapted to decode the first encoded information to generate a second decoded signal; and a second decoding section adapted to generate a third decoded signal by calculating an estimated spectrum in the high frequency band of the input signal based on the second decoded signal and the second encoded information, the estimated spectrum being comprised of an estimation value of a spectrum of each of the N subbands, the estimation value of the first subband being calculated based on the second decoded signal and the second encoded information, and the estimation value of each next of the N subbands being calculated further using the estimation value of its preceding subband, wherein the subbands are obtained by using the second encoded information. a receiving section adapted to receive first encoded information and second encoded information, the first encoded information being generated in a coding apparatus and obtained by encoding a low frequency band of an input signal to be encoded in the coding apparatus equal to or lower than a predetermined frequency, and the second encoded information being generated in the coding apparatus and obtained by dividing a high frequency band of the input signal higher than the predetermined frequency into N subbands, where N is an integer greater than 1, searching for a part of a first decoded signal most similar to a spectrum of the first subband from the N subbands based on the input signal or the first decoded signal, and searching for a part of the decoded signal most similar to a spectrum of each next subband using the search result from its preceding subband, the first decoded signal being obtained by decoding the first encoded information in the coding apparatus; a first decoding section adapted to decode the first encoded information to generate a second decoded signal; and a second decoding section adapted to generate a third decoded signal by calculating an estimated spectrum in the high frequency band of the input signal based on the second decoded signal and the second encoded information, the estimated spectrum being comprised of an estimation value of a spectrum of each of the N subbands, the estimation value of the first subband being calculated based on the second decoded signal and the second encoded information, and the estimation value of each next of the N subbands being calculated further using the estimation value of its preceding subband, wherein the subbands are obtained by using the second encoded information.