A data processing method performed by a computer, comprising steps of: performing detector response calibration based on a detector response obtained by an incidence of rays with known energy into a detector to obtain a detector response model; obtaining a photon counting model of the detector between incident energy spectrum data of the detector and detected energy spectrum data of the detector based on the detector response model; and performing a deconvolution operation on counts of photons in respective energy regions in the detected energy spectrum data of the detector based on the photon counting model of the detector, to obtain real counts of photons in respective energy regions in the incident energy spectrum data of the detector, characterized in that, the deconvolution operation is performed on the counts of photons in respective energy regions in the detected energy spectrum data of the detector for each detector unit and each incident angle of the detector based on the photon counting model of the detector, to obtain real counts of photons in respective energy regions in the incident energy spectrum data of the detector for each detector unit and each incident angle of the detector, wherein all sets of the obtained data are combined to achieve multiple-energy region reconstruction of attenuation coefficient of a substance under inspection detected by the detector, wherein the photon counting model of the detector is as follows: S det E = ∫ E ′ S in E ′ ⋅ h E; E ′ dE ′, where h(E;E') represents the detector response model and means a probability that a photon with energy E' is recorded as energy E, S in (E') represents the incident energy spectrum of the detector, and S det represents detected photons, the detector response model of each energy region is an average of all calibrated monochromatic detector responses contained in the corresponding energy region, and is expressed by the following equation: H k E = ∑ i ∈ ς k α i h E E i wherein represents a set of single energy points contained in the kth energy region, and ∑ i α i = 1 which is a weighted average factor, and the deconvolution operation is performed by an EM solution method. performing detector response calibration based on a detector response obtained by an incidence of rays with known energy into a detector to obtain a detector response model; obtaining a photon counting model of the detector between incident energy spectrum data of the detector and detected energy spectrum data of the detector based on the detector response model; and performing a deconvolution operation on counts of photons in respective energy regions in the detected energy spectrum data of the detector based on the photon counting model of the detector, to obtain real counts of photons in respective energy regions in the incident energy spectrum data of the detector, characterized in that, the deconvolution operation is performed on the counts of photons in respective energy regions in the detected energy spectrum data of the detector for each detector unit and each incident angle of the detector based on the photon counting model of the detector, to obtain real counts of photons in respective energy regions in the incident energy spectrum data of the detector for each detector unit and each incident angle of the detector, wherein all sets of the obtained data are combined to achieve multiple-energy region reconstruction of attenuation coefficient of a substance under inspection detected by the detector, wherein the photon counting model of the detector is as follows: S det E = ∫ E ′ S in E ′ ⋅ h E; E ′ dE ′, where h(E;E') represents the detector response model and means a probability that a photon with energy E' is recorded as energy E, S in (E') represents the incident energy spectrum of the detector, and S det represents detected photons, the detector response model of each energy region is an average of all calibrated monochromatic detector responses contained in the corresponding energy region, and is expressed by the following equation: H k E = ∑ i ∈ ς k α i h E E i wherein represents a set of single energy points contained in the kth energy region, and ∑ i α i = 1 which is a weighted average factor, and the deconvolution operation is performed by an EM solution method.