With respect to the gamma spectrum,the energy resolution improves with increase in energy.The counts of full energy peak change with energy,and this approximately complies with the Gaussian distribution.This study mainly examines a method to deconvolve the LaBr3∶Ce gamma spectrum with a detector response matrix constructing algorithm based on energy resolution calibration.In the algorithm,the full width at half maximum (FWHM) of full energy peak was calculated by the cubic spline interpolation algorithm and calibrated by a square root of a quadratic function that changes with the energy.Additionally,the detector response matrix was constructed to deconvolve the gamma spectrum.Furthermore,an improved SNIP algorithm was proposed to eliminate the background.In the experiment,several independent peaks of 152Eu,137Cs,and 60Co sources were detected by a LaBr3∶Ce scintillator that were selected to calibrate the energy resolution.The Boosted Gold algorithm was applied to deconvolve the gamma spectrum.The results showed that the peak position difference between the experiment and the deconvolution was within-±-2 channels and the relative error of peak area was approximately within 0.96-6.74％.Finally,a 133Ba spectrum was deconvolved to verify the efficiency and accuracy of the algorithm in unfolding the overlapped peaks.